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  • richardmitnick 3:26 pm on May 19, 2017 Permalink | Reply
    Tags: , , Chemists Are One Step Closer to Manipulating All Matter, Controlling a single molecule’s behavior, David Wineland, Laser Technology, ,   

    From WIRED: “Chemists Are One Step Closer to Manipulating All Matter” 

    Wired logo

    WIRED

    Date of Publication: 05.11.17.
    05.11.17
    Nick Stockton

    1
    Getty Images

    For all their periodic tables, styrofoam ball-and-pencil models, and mouth-garbling vocabulary, chemists really don’t know jack about molecules.

    Part of the problem is they can’t really control what molecules do. Molecules spin, vibrate, and trade electrons, all of which affect the way they react with other molecules. Of course, scientists know enough about those scaled-up reactions to do things like make concrete, refine gasoline, and brew beer. But if you’re trying to use individual molecules as tools, or manipulate them so precisely that you can snap them together like Lego pieces, you need better control. Scientists aren’t all the way there yet, but recently scientists at the National Institute of Standards and Technology solved an early challenge: controlling a single molecule’s behavior.

    At the very basic level, controlling a molecule would let scientists learn more about it. “This is a long-standing problem,” says Dietrich Leibfried, a physicist with NIST’s Ion Storage Group in Boulder, Colorado. “Everything around us is made out of molecules, but it’s hard to precisely find out about them.” And that would have practical applications. For instance, NIST keeps tables of molecular properties that astrophysicists consult when they’re reading the spectral signatures of faraway stars and exoplanets. Filling in those blanks would support predictions of whether some exoplanet can support life. With enough control, scientists won’t just get a better look at molecules—they’ll manipulate matter.

    But for now, they are still experimenting. Scientists know how to control atoms using cold vacuum and lasers—so at NIST, scientists’ limited molecular control builds on that knowledge. Their research, published yesterday in Nature, describes their experiment: They begin with a vacuum chamber, a 3-inch box containing a tiny electrode, which itself holds a single positively charged calcium atomic ion. Then come the molecules: Ionized hydrogen gas, which the scientists leak into the vacuum chamber until a single H2 reacts with the calcium atom.

    Now the ionized atom and the ionized molecule are trapped together. But they’re repelled by their positive charges, and the force of the repulsion sends them vibrating—like two magnets when you bring them close. They’re also spinning, like a lopsided barbell hurled into the air.

    So the scientists set out to freeze the pair in place, again calling on their skills of atomic control. First they fire a low-energy laser at the calcium atom, cooling it and stopping its motion—and because it’s coupled to the hydrogen molecule, the hydrogen stops vibrating as well. That’s the easy part. The calcium-hydride is still rotating. “That rotation, the spinning along the horizontal or vertical plane, is the hardest thing to control,” says Leibfried. Imagine trying to stick Legos together if they were spinning independently. Leibfried and his group do know how to stop, and even alter the spinning. They figured that out last year using lasers tuned to specific frequencies.

    All that rigamarole is worthless if you don’t know which way the molecule is pointing, though. And if you want to check in on the molecule—by firing another laser—you set it into random motion once again. So instead the NIST scientists fire a teeny tiny laser at the calcium atom, causing it to wiggle. Because it is connected to the hydrogen molecule, it picks up on the molecule’s state. And Leibfried and his team can “read” that state by examining the way the laser’s light scatters when it encounters the calcium atom. The whole intricate choreography between them lasts about a millisecond, and at the end they can see if the molecule behaved as it was directed.

    So what’s the point of all that? If you can control with certainty the orientation of a molecule, it’s one step closer to sticking them together exactly how you want—no more tossing compounds in a beaker and praying for the right kind of bubbles. Or, to return to the Lego analogy, you can understand—and manipulate—how molecules stick together.

    This discovery builds off work done by Leibfried’s mentor, Nobel winner David Wineland, who did the foundational atomic control work behind atomic clocks based on single trapped ions. But unlike atomic clocks—which changed the scale at which scientists could measure time, and led to breakthroughs like GPS—this process isn’t ready to revolutionize chemistry just yet. Scientists need to fine-tune their control, and have yet to proof the concept on molecules besides hydrogen. Having just one molecule would be like trying to build a city from Legos using only 2×4 bricks.

    See the full article here .

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  • richardmitnick 5:21 am on May 16, 2017 Permalink | Reply
    Tags: , Laser Technology, LLNL NIF, , Particle acceleration, , Rochester’s Laboratory for Laser Energetics, SLAC National Accelerator Laboratory   

    From ALCF: “Fields and flows fire up cosmic accelerators” 

    Argonne Lab
    News from Argonne National Laboratory

    ANL Cray Aurora supercomputer
    Cray Aurora supercomputer at the Argonne Leadership Computing Facility

    MIRA IBM Blue Gene Q supercomputer at the Argonne Leadership Computing Facility
    MIRA IBM Blue Gene Q supercomputer at the Argonne Leadership Computing Facility

    ALCF

    May 15, 2017
    John Spizzirri

    1
    A visualization from a 3D OSIRIS simulation of particle acceleration in laser-driven magnetic reconnection. The trajectories of the most energetic electrons (colored by energy) are shown as the two magnetized plasmas (grey isosurfaces) interact. Electrons are accelerated by the reconnection electric field at the interaction region and escape in a fan-like profile. Credit: Frederico Fiuza, SLAC National Accelerator Laboratory/OSIRIS

    Every day, with little notice, the Earth is bombarded by energetic particles that shower its inhabitants in an invisible dusting of radiation, observed only by the random detector, or astronomer, or physicist duly noting their passing. These particles constitute, perhaps, the galactic residue of some far distant supernova, or the tangible echo of a pulsar. These are cosmic rays.

    But how are these particles produced? And where do they find the energy to travel unchecked by immense distances and interstellar obstacles?

    These are the questions Frederico Fiuza has pursued over the last three years, through ongoing projects at the Argonne Leadership Computing Facility (ALCF), a U.S. Department of Energy (DOE) Office of Science User Facility.

    A physicist at the SLAC National Accelerator Laboratory in California, Fiuza and his team are conducting thorough investigations of plasma physics to discern the fundamental processes that accelerate particles.

    The answers could provide an understanding of how cosmic rays gain their energy and how similar acceleration mechanisms could be probed in the laboratory and used for practical applications.

    While the “how” of particle acceleration remains a mystery, the “where” is slightly better understood. “The radiation emitted by electrons tells us that these particles are accelerated by plasma processes associated with energetic astrophysical objects,” says Fiuza.

    The visible universe is filled with plasma, ionized matter formed when gas is super-heated, separating electrons from ions. More than 99 percent of the observable universe is made of plasmas, and the radiation emitted from them creates the beautiful, eerie colors that accentuate nebulae and other astronomical wonders.

    The motivation for these projects came from asking whether it was possible to reproduce similar plasma conditions in the laboratory and study how particles are accelerated.

    High-power lasers, such as those available at the University of Rochester’s Laboratory for Laser Energetics or at the National Ignition Facility in the Lawrence Livermore National Laboratory, can produce peak powers in excess of 1,000 trillion watts.

    2
    Rochester’s Laboratory for Laser Energetics


    At these high-powers, lasers can instantly ionize matter and create energetic plasma flows for the desired studies of particle acceleration.

    Intimate Physics

    To determine what processes can be probed and how to conduct experiments efficiently, Fiuza’s team recreates the conditions of these laser-driven plasmas using large-scale simulations. Computationally, he says, it becomes very challenging to simultaneously solve for the large scale of the experiment and the very small-scale physics at the level of individual particles, where these flows produce fields that in turn accelerate particles.

    Because the range in scales is so dramatic, they turned to the petascale power of Mira, the ALCF’s Blue Gene/Q supercomputer, to run the first-ever 3D simulations of these laboratory scenarios. To drive the simulation, they used OSIRIS, a state-of-the-art, particle-in-cell code for modeling plasmas, developed by UCLA and the Instituto Superior Técnico, in Portugal, where Fiuza earned his PhD.

    Part of the complexity involved in modeling plasmas is derived from the intimate coupling between particles and electromagnetic radiation — particles emit radiation and the radiation affects the motion of the particles.

    In the first phase of this project, Fiuza’s team showed that a plasma instability, the Weibel instability, is able to convert a large fraction of the energy in plasma flows to magnetic fields. They have shown a strong agreement in a one-to-one comparison of the experimental data with the 3D simulation data, which was published in Nature Physics, in 2015. This helped them understand how the strong fields required for particle acceleration can be generated in astrophysical environments.

    Fiuza uses tennis as an analogy to explain the role these magnetic fields play in accelerating particles within shock waves. The net represents the shockwave and the racquets of the two players are akin to magnetic fields. If the players move towards the net as they bounce the ball between each other, the ball, or particles, rapidly accelerate.

    “The bottom line is, we now understand how magnetic fields are formed that are strong enough to bounce these particles back and forth to be energized. It’s a multi-step process: you need to start by generating strong fields — and we found an instability that can generate strong fields from nothing or from very small fluctuations — and then these fields need to efficiently scatter the particles,” says Fiuza.

    Reconnecting

    NASA Magnetic reconnection, Credit: M. Aschwanden et al. (LMSAL), TRACE, NASA

    But particles can be energized in another way if the system provides the strong magnetic fields from the start.

    “In some scenarios, like pulsars, you have extraordinary magnetic field amplitudes,” notes Fiuza. “There, you want to understand how the enormous amount of energy stored in these fields can be directly transferred to particles. In this case, we don’t tend to think of flows or shocks as the dominant process, but rather magnetic reconnection.”

    Magnetic reconnection, a fundamental process in astrophysical and fusion plasmas, is believed to be the cause of solar flares, coronal mass ejections, and other volatile cosmic events. When magnetic fields of opposite polarity are brought together, their topologies are changed. The magnetic field lines rearrange in such a way as to convert magnetic energy into heat and kinetic energy, causing an explosive reaction that drives the acceleration of particles. This was the focus of Fiuza’s most recent project at the ALCF.

    Again, Fiuza’s team modeled the possibility of studying this process in the laboratory with laser-driven plasmas. To conduct 3D, first-principles simulations (simulations derived from fundamental theoretical assumptions/predictions), Fiuza needed to model tens of billions of particles to represent the laser-driven magnetized plasma system. They modeled the motion of every particle and then selected the thousand most energetic ones. The motion of those particles was individually tracked to determine how they were accelerated by the magnetic reconnection process.

    “What is quite amazing about these cosmic accelerators is that a very, very small number of particles carry a large fraction of the energy in the system, let’s say 20 percent. So you have this enormous energy in this astrophysical system, and from some miraculous process, it all goes to a few lucky particles,” he says. “That means that the individual motion of particles and the trajectory of particles are very important.”

    The team’s results, which were published in Physical Review Letters, in 2016, show that laser-driven reconnection leads to strong particle acceleration. As two expanding plasma plumes interact with each other, they form a thin current sheet, or reconnection layer, which becomes unstable, breaking into smaller sheets. During this process, the magnetic field is annihilated and a strong electric field is excited in the reconnection region, efficiently accelerating electrons as they enter the region.

    Fiuza expects that, like his previous project, these simulation results can be confirmed experimentally and open a window into these mysterious cosmic accelerators.

    This research is supported by the DOE Office of Science. Computing time at the ALCF was allocated through the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program.

    See the full article here .

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    Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.

    About ALCF

    The Argonne Leadership Computing Facility’s (ALCF) mission is to accelerate major scientific discoveries and engineering breakthroughs for humanity by designing and providing world-leading computing facilities in partnership with the computational science community.

    We help researchers solve some of the world’s largest and most complex problems with our unique combination of supercomputing resources and expertise.

    ALCF projects cover many scientific disciplines, ranging from chemistry and biology to physics and materials science. Examples include modeling and simulation efforts to:

    Discover new materials for batteries
    Predict the impacts of global climate change
    Unravel the origins of the universe
    Develop renewable energy technologies

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    Argonne Lab Campus

     
  • richardmitnick 9:08 am on May 10, 2017 Permalink | Reply
    Tags: A laser-guided path to diamond superconductors?, , , Laser Technology, Raman spectroscopy,   

    From COSMOS: “A laser-guided path to diamond superconductors?” 

    Cosmos Magazine bloc

    COSMOS

    10 May 2017
    Andrew Stapleton

    1
    A diamond, recently. Mina De La O / Getty

    Besides glittering beautifully in the sun, diamonds have another attractive property: they can become superconductive. Superconductivity occurs when a material has zero electrical resistance and is normally only seen when the material is chilled to temperatures very close to absolute zero (around –273 °C), which severely limits the use of superconductors in commercial applications.

    Scientists from India and Israel conducted the first systematic study to understand how doping diamond with boron effects its ability to become superconducting. They reported their findings in Applied Physics Letters.

    The scientists fabricated a series of thin diamond films doped with increasing levels of boron and monitored the samples with a technique called Raman spectroscopy. This technique uses pulses of laser light at specific wavelengths to measure the unique energy states in materials. Raman spectroscopy can be used for analysing the makeup of material or, as in this study, to watch how the energy states are affected by impurities.

    Associate Professor Rongkun Zheng of the University of Sydney, a physicist not involved with the study, said: “Raman scattering probes the vibration and rotation of atoms or molecules in a sample, which is related to the superconductivity of the material.”

    The team noticed a remarkable change in the energy states of the doped diamond. They concluded that their study provided a new understanding of how impurities effect the energy levels in diamonds and, perhaps more tenuously, that this could lead to a superconductive material that doesn’t have to be chilled to absolute zero.

    The results, they believe, could inform the fabrication of materials for future applications such as high-performance electrical grids and high-speed transport.

    Zheng, however, is less convinced. “The paper emphasised superconductivity but did not explore the effect on superconductivity. The significance and quality of this paper is very limited.”

    See the full article here .

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  • richardmitnick 8:27 am on April 21, 2017 Permalink | Reply
    Tags: , Laser Technology, Polarization states,   

    From UCLA: “UCLA-led team develops technique to control laser polarization” 

    UCLA bloc

    UCLA

    April 19, 2017
    Matthew Chin

    1
    Artist’s depiction of the laser polarization metasurface that can tune the laser’s polarization state purely electronically, without any moving parts. Nicoletta Barolini/UCLA

    A research team led by UCLA electrical engineers has developed a new technique to control the polarization state of a laser that could lead to a new class of powerful, high-quality lasers for use in medical imaging, chemical sensing and detection, or fundamental science research.

    Think of polarized sunglasses, which help people see more clearly in intense light. Polarizing works by filtering visible light waves to allow only waves that have their electric field pointing in one specific direction to pass through, which reduces brightness and glare.

    Like brightness and color, polarization is a fundamental property of light that emerges from a laser. The traditional way to control the polarization of a laser was to use a separate component like a polarizer or a waveplate. To change its polarization, the polarizer or waveplate must be physically rotated, a slow process that results in a physically larger laser system.

    The team from the UCLA Henry Samueli School of Engineering and Applied Science developed a specialized artificial material, a type of “metasurface,” that can tune the laser’s polarization state purely electronically, without any moving parts. The research was published in Optica. The breakthrough advance was applied to a class of lasers in the terahertz range of frequencies on the electromagnetic spectrum, which lies between microwaves and infrared waves.

    “While there are a few ways to quickly switch polarization in the visible spectrum, in the terahertz range there is currently a lack of good options,” said Benjamin Williams, associate professor of electrical engineering and the principal investigator of the research. “In our approach, the polarization control is built right into the laser itself. This allows a more compact and integrated setup, as well as the possibility for very fast electronic switching of the polarization. Also, our laser efficiently generates the light into the desired polarization state — no laser power is wasted generating light in the wrong polarization.”

    Terahertz radiation penetrates many materials, such as dielectric coatings, paints, foams, plastics, packaging materials, and more without damaging them, Williams said.

    “So some applications include non-destructive evaluation in industrial settings, or revealing hidden features in the study of art and antiquities,” said Williams, who directs the Terahertz Devices and Intersubband Nanostructures Laboratory. “For example, our laser could be used for terahertz imaging, where the addition of polarization contrast may help to uncover additional information in artwork, such as improved edge detection for hidden defects or structures.”

    The work is based on the group’s recent development of the world’s first vertical-external-cavity surface-emitting laser, or VECSEL, that operates in the terahertz range.

    Their new metasurface covers an area of 2 square millimeters and has a distinct zigzag pattern of wire antennas running across its surface. An electric current runs through the wires, selectively energizing particular segments of the laser material, which allows a user to change and customize the polarization state as needed.

    The lead authors of the research are electrical engineering graduate student Luyao Xu and electrical engineering undergraduate student Daguan Chen. Other authors include electrical engineering graduate student Christopher Curwen; Mohammad Memarian, a postdoctoral scholar in UCLA’s microwave electronics lab; John Reno of Sandia National Laboratories; and UCLA electrical engineering professor Tatsuo Itoh, who holds the Northrop Grumman Chair in Engineering.

    The research was supported by the National Science Foundation and NASA.

    See the full article here .

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    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 11:52 am on March 1, 2017 Permalink | Reply
    Tags: , Laser Technology, , Scientists develop spectacles for X-ray lasers, X-ray laser beam,   

    From DESY: “Scientists develop spectacles for X-ray lasers” 

    DESY
    DESY

    2017/03/01

    Tailor-made corrective glasses permit unparalleled concentration of X-ray beam

    An international team of scientists has tailored special X-ray glasses to concentrate the beam of an X-ray laser stronger than ever before. The individually produced corrective lens eliminates the inevitable defects of an X-ray optics stack almost completely and concentrates three quarters of the X-ray beam to a spot with 250 nanometres (millionths of a millimetre) diameter, closely approaching the theoretical limit. The concentrated X-ray beam can not only improve the quality of certain measurements, but also opens up entirely new research avenues, as the team surrounding DESY lead scientist Christian Schroer writes in the journal Nature Communications.

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    Profile of the focused X-ray beam, without (top) and with (bottom) the corrective lens. Credit: Frank Seiboth, DESY

    Although X-rays obey the same optical laws as visible light, they are difficult to focus or deflect: “Only a few materials are available for making suitable X-ray lenses and mirrors,” explains co-author Andreas Schropp from DESY. “Also, since the wavelength of X-rays is very much smaller than that of visible light, manufacturing X-ray lenses of this type calls for a far higher degree of precision than is required in the realm of optical wavelengths – even the slightest defect in the shape of the lens can have a detrimental effect.”

    The production of suitable lenses and mirrors has already reached a very high level of precision, but the standard lenses, made of the element beryllium, are usually slightly too strongly curved near the centre, as Schropp notes. “Beryllium lenses are compression-moulded using precision dies. Shape errors of the order of a few hundred nanometres are practically inevitable in the process.” This results in more light scattered out of the focus than unavoidable due to the laws of physics. What’s more, this light is distributed quite evenly over a rather large area.

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    The X-ray spectacles under an electron microscope. Credit: DESY NanoLab

    Such defects are irrelevant in many applications. “However, if you want to heat up small samples using the X-ray laser, you want the radiation to be focussed on an area as small as possible,” says Schropp. “The same is true in certain imaging techniques, where you want to obtain an image of tiny samples with as much details as possible.”

    In order to optimise the focussing, the scientists first meticulously measured the defects in their portable beryllium X-ray lens stack. They then used these data to machine a customised corrective lens out of quartz glass, using a precision laser at the University of Jena. The scientists then tested the effect of these glasses using the LCLS X-ray laser at SLAC National Accelerator Laboratory in the U.S.

    “Without the corrective glasses, our lens focused about 75 per cent of the X-ray light onto an area with a diameter of about 1600 nanometres. That is about ten times as large as theoretically achievable,” reports principal author Frank Seiboth from the Technical University of Dresden, who now works at DESY. “When the glasses were used, 75 per cent of the X-rays could be focused into an area of about 250 nanometres in diameter, bringing it close to the theoretical optimum.” With the corrective lens, about three times as much X-ray light was focused into the central speckle than without it. In contrast, the full width at half maximum (FWHM), the generic scientific measure of focus sharpness in optics, did not change much and remained at about 150 nanometres, with or without the glasses.

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    Scheme of the experimental set-up. Credit: Frank Seiboth, DESY

    The same combination of mobile standard optics and tailor-made glasses has also been studied by the team at DESY’s synchrotron X-ray source PETRA III and the British Diamond Light Source. In both cases, the corrective lens led to a comparable improvement to that seen at the X-ray laser. “In principle, our method allows an individual corrective lens to be made for every X-ray optics,” explains lead scientist Schroer, who is also a professor of physics at the University of Hamburg.

    “These so-called phase plates can not only benefit existing X-ray sources, but in particular they could become a key component of next-generation X-ray lasers and synchrotron light sources,” emphasises Schroer. “Focusing X-rays to the theoretical limits is not only a prerequisite for a substantial improvement in a range of different experimental techniques; it can also pave the way for completely new methods of investigation. Examples include the non-linear scattering of particles of light by particles of matter, or creating particles of matter from the interaction of two particles of light. For these methods, the X-rays need to be concentrated in a tiny space which means efficient focusing is essential.”

    Involved in this research project were the Technical University of Dresden, the Universities of Jena and Hamburg, KTH Royal Institute of Technology in Stockholm, Diamond Light Source, SLAC National Accelerator Laboratory and DESY.

    See the full article here .

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    desi

    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

     
  • richardmitnick 3:29 pm on February 2, 2017 Permalink | Reply
    Tags: , Department of Energy fusion laser research and development, Diode-pumped petawatt lasers, ELI Beamlines - European Extreme Light Infrastructure Beamlines, High-Repetition-Rate Advanced Petawatt Laser System (HAPLS), Laser Technology,   

    From LLNL: “LLNL meets key milestone for delivery of world’s highest average power petawatt laser system” This is a Big Deal 


    Lawrence Livermore National Laboratory

    Feb. 2, 2017

    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    [THIS IS A BIG DEAL, US DEVELOPED TECHNOLOGY FOR EXPORT.]

    1
    HAPLS has set a world record for diode-pumped petawatt lasers, with energy reaching 16 joules and a 28 femtosecond pulse duration (equivalent to ~0.5 petawatt/pulse) at a 3.3 hertz repetition rate (3.3 times per second).

    The High-Repetition-Rate Advanced Petawatt Laser System (HAPLS), being developed at Lawrence Livermore National Laboratory (LLNL), recently completed a significant milestone: demonstration of continuous operation of an all diode-pumped, high-energy femtosecond petawatt laser system.

    With completion of this milestone, the system is ready for delivery and integration at the European Extreme Light Infrastructure Beamlines facility project (ELI Beamlines) in the Czech Republic.

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    e
    ELI Beamlines

    HAPLS set a world record for diode-pumped petawatt lasers, with energy reaching 16 joules (J) and a 28 femtosecond (fs) pulse duration (equivalent to ~0.5 petawatt/pulse) at a 3.3 hertz (Hz) repetition rate (3.3 times per second).

    In just three years, HAPLS went from concept to a fully integrated and record-breaking product. HAPLS represents a new generation of application-enabling diode-pumped, high-energy and high-peak-power laser systems with innovative technologies originating from the Department of Energy fusion laser research and development.

    “Lawrence Livermore takes pride in pushing science and technology to regimes never achieved before,” LLNL Director Bill Goldstein said. “Twenty years ago, LLNL pioneered the first petawatt laser, the NOVA Petawatt, representing a quantum leap forward in peak power. Today, HAPLS leads a new generation of petawatt lasers, with capabilities not seen before.”

    6
    The Nova laser at Lawrence Livermore National Laboratory in California, completed in 1984, was the world’s largest working laser until its retirement in 1999. With 10 laser beams, it was used for experiments on x-rays, astronomical phenomena, and fusion energy. In 1996, it was made into a petawatt laser, in which a short, intense pulse produced the highest power yet achieved: about 1.3 petawatts, or 1.3 quadrillion watts.

    In the decades since high-power lasers were introduced, they have illuminated entirely new fields of scientific endeavor, in addition to making profound impacts on society. When petawatt peak power pulses are focused to a high intensity on a target, they generate secondary sources such as electromagnetic radiation (for example, high-brightness X-rays) or accelerate charged particles (electrons, protons or ions), enabling unparalleled access to a variety of research areas, including time-resolved proton and X-ray radiography, laboratory astrophysics and other basic science and medical applications for cancer treatments, in addition to national security applications and industrial processes such as nondestructive evaluation of materials and laser fusion.

    Up to now, proof-of-principle experiments with single-shot lasers have provided a glimpse into this arena of transformational applications, but to commercially explore these areas a high-repetition-rate petawatt laser is needed.

    “The high-repetition-rate of the HAPLS system is a watershed moment for the community,” said Constantin Haefner, LLNL’s program director for Advanced Photon Technologies (APT). “HAPLS is the first petawatt laser to truly provide application-enabling repetition rates.”

    Drawing on LLNL’s decades of cutting-edge laser research and development led to the key advancements that distinguish HAPLS from other petawatt lasers. Those advancements include HAPLS’ ability to reach petawatt power levels while maintaining an unprecedented pulse rate; development of the world’s highest peak power diode arrays…

    5
    To drive the diode arrays, LLNL needed to develop a completely new type of pulsed-power system, which supplies the arrays with electrical power by drawing energy from the grid and converting it to extremely high-current, precisely-shaped electrical pulses.Photos by Damien Jemison.

    …driven by a Livermore-developed pulsed power system; a pump laser generating up to 200 J at a 10 Hz repetition rate; a gas-cooled short-pulse titanium-doped sapphire amplifier; a sophisticated control system with a high level of automation including auto-alignment capability, fast laser startup, performance tracking and machine safety; dual chirped-pulse-amplification high-contrast short-pulse front end; and a gigashot laser pump source for pumping the short-pulse preamplifiers. In addition, HAPLS is to be the most compact petawatt laser ever built.

    This expertise is why ELI Beamlines looked to Livermore to develop HAPLS. “It was quite straightforward,” said Roman Hvezda, ELI Beamlines project manager. “Given the design requirements, nobody else could deliver this system in such a short time on schedule and on budget. It’s a great benefit to be able to cooperate with Livermore, a well-established lab, and this will be a basis for continued cooperation in the future.”

    This cooperation was daily during construction, with LLNL and ELI Beamlines scientists and engineers working side by side on all parts of the laser system.

    “One of the real successes of this endeavor was that very early on, the client was fully integrated into the commissioning and operation of this laser,” Haefner said. “This provided hands-on training and expertise right out of the gate, helping to ensure operational success once the laser is installed at ELI Beamlines. We look at this as a long-term and enduring partnership.”

    Bedrich Rus, ELI Beamlines scientific coordinator for Laser Technology, agrees. “This was never a standard client-supplier relationship,” he said. “We have had about 10 people at LLNL – this integration is not only a very positive added value for the future operation of the facility, it’s been a great experience for their careers and development.”

    In the coming months, HAPLS will be transferred to ELI Beamlines, where it will be integrated into the facility’s laser beam transport and control systems, then brought up to full design specification – delivery of pulses with peak power exceeding 1 petawatt (quadrillion watts) firing at 10 Hz, breaking its own record and making it the world’s highest average power petawatt system. ELI plans to make HAPLS available by 2018 to the international science user community to conduct the first experiments using the laser.

    “HAPLS was a very fast-paced project,” Haefner said. “In only three years it pushed the cutting edge in high-power short-pulse lasers more than tenfold, incorporating a completely new system approach. To do so, Livermore worked closely with industry to similarly advance the state of the art – and many of those joint Livermore/industry innovations are already on the market. These partnerships can be incredibly synergistic, resulting in successful and societal impactful technologies like HAPLS.”

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  • richardmitnick 10:26 am on January 26, 2017 Permalink | Reply
    Tags: , Britain's Central Laser Facility (CLF), DiPOLE 100 laser, HiLASE's plan for the laser, Laser Technology,   

    From Science Alert: “Scientists claim they’ve built the most powerful pulse laser on Earth” 

    ScienceAlert

    Science Alert

    25 JAN 2017
    BEC CREW

    1
    Georgy Shafeev/Shutterstock,com

    This we need to see.

    Scientists say they’ve successfully tested a new US$48 million ‘super laser’, and they’re claiming it’s 10 times more powerful than any other laser of its kind on the planet, with an average power output of 1,000 watts.

    If that doesn’t sound all that powerful to you, you’re right – there’s a laser in Japan that can hit peak outputs of more than 1 trillion watts. But this new pulse laser doesn’t blow everything on a single burst – it can reportedly fire high-powered beams many times over, and with more power than any other technology on the planet.

    The laser has been built by Britain’s Central Laser Facility (CLF), and HiLASE (High average power pulsed laser), a Czech state research and development project run by the country’s Institute of Physics.

    “It is a world record which is important,” director of the CLF, John Collier, told AFP.

    “It is good for putting things on the map, but the more important point is that the underlying technology that has been developed here is going to transform the application of these high power, high energy lasers.”

    Let’s get one thing straight right off the bat – a world record is a mighty big claim, and the team has yet to release a peer-reviewed paper to support it. So until the numbers are independently verified, we’ll have to take their word for it, but it’s by no means official.

    But the Czech researchers have had a plan in place to hit this specific record since 2011, and Central Laser Facility has been developing laser technology for over four decades now, and currently have five active laser labs in operation, so these are not new players in the laser game.

    The team claims to have achieved the record last month at a testing facility in Dolní Břežany – a municipality near Prague in the Czech Republic.

    Their DiPOLE 100 laser (nicknamed Bivoj, after a Hercules-like hero in Czech mythology), reportedly hit an average of 1,000 watts for over 1 hour without intervention, and the team asserts that this kind of sustained, high-energy pulsing is unrivalled.

    When we talk about the world’s most powerful lasers, there are two very different types – there are continuous lasers, which fire constant beams of energy, and there are pulse lasers, which can fire in short, powerful bursts.

    The DiPOLE 100 is a pulse laser, and the two other largest high-power pulse lasers in existence are the Texas Petawatt Laser in Austin, and the 2-petawatt Laser for Fast Ignition Experiments (LFEX) in Osaka, Japan.

    Those lasers “have a very high peak power, but they can only reach it several times a day,” HiLASE director Tomas Mocek told AFP.

    “They do not have so-called average power. This is a combination of the repetition rate and the energy. Our laser has the highest average power, which is important. The repetition rate in Osaka and Austin is significantly lower.”

    What’s really cool about this announcement – if it can be confirmed in a published paper – is that it adds a new kind of diversity to the world’s best high-powered pulse lasers, and could be really useful for researchers of the future.

    So while the Texas Petawatt Laser could be used to run a couple of experiments per day, helping researchers peer into exotic states of matter and ultra-high electromagnetic fields, the DiPOLE 100 provides a constant stream of highly focussed laser energy for things like particle acceleration and X-ray generation.

    The team plans on commercialising it by the end of 2017, so let’s hope some great science comes of it.

    For more information on the project, you can check out HiLASE’s plan for the laser.

    See the full article here .

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  • richardmitnick 3:35 pm on December 6, 2016 Permalink | Reply
    Tags: , Laser Technology,   

    From Technion via Futurism: “Scientists Have Created a Totally New Type of Laser With Light and Water Waves” 

    Technion bloc

    Technion

    1

    Futurism

    12.6.16
    Dom Galeon

    In Brief

    Using a device smaller than the width of a human hair, scientists have produced laser radiation through the interaction of light and water waves, a first in the field of laser tech.
    This new type of laser could be used on tiny ‘lab-on-a-chip’ technologies, enabling researchers to more effectively study microscopic cells and test different drug therapies.

    Of Waves and Lightwaves

    There’s a new kid in town with respect to laser technology. Researchers at the Technion–Israel Institute of Technology have developed laser emissions through the interaction of light and water waves, combining two areas of study previously thought unrelated.

    Typically, lasers are produced by exciting electrons in atoms using energy from an outside source. This excitement causes the electrons to emit radiation as laser light. The Technion team, led by Tal Carmon, discovered that wave oscillations in a liquid device can produce laser radiation as well, according to the study published in Nature Photonics.

    This possibility had never been explored previously, Carmon told Phys.org, primarily due to enormous differences in frequencies between water waves on a liquid’s surface and light wave oscillations. The former have a low frequency of approximately 1,000 oscillations per second, while the latter have a higher frequency of around 1014 oscillations per second.

    The researchers built a device that used an optical fiber to deliver light into a small droplet of octane and water. It compensated for the otherwise low efficiency between light waves and water waves, allowing the two types to pass through each other approximately 1 million times within the droplet. The energy generated by this interaction leaves the droplet as the laser emission.

    2
    Credits: The Technion-Israel Institute of Technology

    Greater Control

    This interaction between light and fluid happens on a scale smaller than the width of a human hair. Additionally, water is a million times softer than typical materials used in existing laser technology. Accordingly, the Technion researchers say the droplet deformation caused by this very small pressure from the the light is a million times greater than what’s seen in current optomechanical devices, so this laser tech would be easier to control.

    Because they would work on such a small scale and be easier to control, this new type of laser could open up a wealth of possibilities for tiny sensors that use a combination of light waves, water waves, and sound waves. They could be used on tiny ‘lab-on-a-chip’ technologies, enabling researchers to more effectively study microscopic cells and test different drug therapies that could lead to better healthcare down the road. Indeed, these tiny lasers could have big implications in the world of technology.

    See the full article here .

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    Technion Campus

    A science and technology research university, among the world’s top ten,
    dedicated to the creation of knowledge and the development of human capital and leadership,
    for the advancement of the State of Israel and all humanity.

     
  • richardmitnick 8:34 am on September 30, 2016 Permalink | Reply
    Tags: , Laser Technology, , Physicists have figured out how to create matter and antimatter using light,   

    From Science Alert: “Physicists have figured out how to create matter and antimatter using light” 

    ScienceAlert

    Science Alert

    1
    Wikimedia Commons

    29 SEP 2016
    JUNE JAVELOSA, FUTURISM

    A team of researchers from the Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS) has just announced that they managed to calculate how to create matter and antimatter using lasers.

    This means that, by focusing high-powered laser pulses, we might soon be able to create matter and antimatter using light.

    To break this down a bit, light is made of high-energy photons. When high-energy photons go through strong electric fields, they lose enough radiation that they become gamma rays and create electron-positron pairs, thus creating a new state of matter.

    “A strong electric field can, generally speaking, ‘boil the vacuum,’ which is full of ‘virtual particles,’ such as electron-positron pairs. The field can convert these types of particles from a virtual state, in which the particles aren’t directly observable, to a real one,” says Igor Kostyukov of IAP RAS, who references their calculations on the concept of quantum electrodynamics (QED).

    2
    NASA Astrophysics

    A QED cascade is a series of processes that starts with electrons and positrons accelerating within a laser field. It will then be followed by the release of high-energy photons, electrons, and positrons.

    As high-energy photons decay, it will produce electron-positron pairs. Essentially, a QED cascade will lead to the production of electron positron high-energy photon plasmas – and while it perfectly illustrates the QED phenomenon, it is a theory that has yet to be observed under lab conditions.

    Based on this, researchers observed how intense laser pulses would interact with a foil via numerical simulations. Surprisingly, they discovered that there were more high-energy photons produced by the positrons versus electrons produced of the foil.

    And if you could produce a massive number of positrons via a corresponding experiment, you can conclude that most were generated via a QED cascade.

    As complicated as all that sounds, here’s the bottom line – this discovery can open new doors in terms of how we can efficiently and cost-effectively produce matter and antimatter, the latter of which can significantly change the way we power our spaceships.

    As has been previously noted, making this potential power source is not cheap:

    “The problem lies in the efficiency and cost of antimatter production and storage. Making 1 gram of antimatter would require approximately 25 million billion kilowatt-hours of energy and cost over a million billion dollars.”

    This work offers us a new way forward.

    Their study also offers major insight into the properties of different types of interactions that could eventually pave the way for practical applications, including the development of advanced ideas for the laser-plasma sources of high-energy photons and positrons that will exceed the brilliance of any available source we have today.

    “Next, we’re exploring the nonlinear stage when the self-generated electron-positron plasma strongly modifies the interaction,” the researchers add.

    “And we’ll also try to expand our results to more general configurations of the laser-matter interactions and other regimes of interactions – taking a wider range of parameters into consideration.”

    This article was originally published by Futurism.

    See the full article here .

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  • richardmitnick 3:04 pm on July 18, 2016 Permalink | Reply
    Tags: 3D printing could revolutionize laser design, Laser Technology,   

    From LLNL: “3D printing could revolutionize laser design” 


    Lawrence Livermore National Laboratory

    Jul. 18, 2016
    Jeremy Thomas
    thomas244@llnl.gov
    925-422-5539

    1
    Ibo Matthews inspects an in situ diagnostics test bench his team developed for studying laser-driven powder bed fusion additive manufacturing. High-speed thermal and optical mapping of the laser-powder interaction has enabled the team to reveal new physics associated with the process and helped guide high-performance computing simulations. Photo by Julie Russell.

    LLNL researchers are exploring the use of metal 3D printing to create strong, lightweight structures for advanced laser systems – an effort they say could alter the way lasers are designed in the future.

    In a Laboratory Directed Research and Development (LDRD) program, physicist Ibo Matthews and his team are experimenting with a new research-based metal 3D printer, one of only four of its kind in the world, using a customized software platform capable of unprecedented design control.

    The powder bed laser-melting printer, made by the Fraunhofer Institute for Laser Technology (ILT) and German startup Aconity 3D, was installed in December 2015. Lab engineers have added diagnostics and high-speed cameras to examine thermal emissions and to image the surface of parts as they’re being built. Matthews said the modifications will help the researchers determine how defects or deformations occur during the 3D printing process.

    “It’s very flexible; it allows us to change any of the parameters we want,” he said. “We’re developing confidence in what we’ve built. If any defects occur, it is our aim that the user can have a 3D map available at the end of the build that shows what and where it happened.”

    Matthews and his team are building on their experience in laser materials processing and interaction gained in support of both the National Ignition Facility (NIF) and directed energy projects to develop new approaches to metal 3D printing. Their work is part of an overall strategy to broaden the NIF & Photon Science (NIF&PS) laser applications portfolio and maintain core competencies in laser-matter interaction science. Moreover, NIF scientists are intrigued by the potential for the metal 3D printing platform to support lasers – not just at NIF, but in airborne systems that need to be extremely lightweight, such as those used for remote sensing and aerial scanning.

    “With precision, predictive control of 3D printing you can put the stiffness where you need it,” said Mike Carter, NIF&PS program director for Department of Defense Technologies. “You can create functionally graded structures for optical lasers and mounts that are impossible to make by conventional manufacturing methods.”

    NIF has utilized some metal parts printed at the Lab in structures for lasers. In order to use them in critical systems on a regular basis, however, researchers must be assured that each part is sound.

    To speed up the certification process, Lab engineers are attempting to shorten the development phase by taking a completely different approach – a “feed-forward” method based on computer modeling instead of trial and error. If successful, said Wayne King of LLNL’s Physical and Life Sciences Directorate, the research could fundamentally change the way metal components – including those used in optical systems – are designed and fabricated.

    “Unless you take a science-based approach to this, you won’t know why part A is different from part B,” King said. “We’re really pushing the state of the art. We’re at the beginning of seeing some applications of the technology already.”

    In the three-year LDRD project that began last year, Matthews and his team will be combining metal 3D printing with both high-fidelity optical diagnostics and high-performance computing to create more confidence in the parts they create.

    “What we’d like to do is drive this process based on simulation, and create a ‘digital fingerprint’ of certification based on optical monitoring to ensure the part is built right the first time,” Matthews said. “We’d like to be predictive, based on our physics models, to find out what we can expect with any given build and have monitoring data to show that predictions matched the outcome.”

    Matthews added that the Lab’s newest machine will go a long way toward discovering the capabilities and application of metal 3D printing for laser design.

    “It takes you from this black box to something you have control over,” he said. “It puts us two years ahead of where we would’ve been if we hadn’t bought it.”

    NIF&PS and the Lab’s Weapons and Complex Integration and Engineering directorates are jointly supporting the new printing platform.

    See the full article here .

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