From CSIROscope: “Explainer: what happens when magnetic north and true north align?”

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From CSIROscope

17 September 2019
Paul Wilkes

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Very rarely, depending on where you are in the world, your compass can actually point to true north. Image: Shutterstock

At some point in recent weeks, a once-in-a-lifetime event happened for people at Greenwich in the United Kingdom.

Magnetic compasses at the historic London area, known as the home of the Prime Meridian, were said to have pointed directly at the north geographic pole for the first time in 360 years.

This means that, for someone at Greenwich, magnetic north (the direction in which a compass needle points) would have been in exact alignment with geographic north.

Geographic north (also called “true north”) is the direction towards the fixed point we call the North Pole.

Magnetic north is the direction towards the north magnetic pole, which is a wandering point where the Earth’s magnetic field goes vertically down into the planet.

The north magnetic pole is currently about 400km south of the north geographic pole, but can move to about 1,000km away.

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The lines of the Earth’s magnetic field come vertically out of the Earth at the south magnetic pole and go vertically down into the Earth at the north magnetic pole. Image: Nasky/Shutterstock

How do the norths align?

Magnetic north and geographic north align when the so-called “angle of declination”, the difference between the two norths at a particular location, is 0°.

Declination is the angle in the horizontal plane between magnetic north and geographic north. It changes with time and geographic location.

On a map of the Earth, lines along which there is zero declination are called agonic lines. Agonic lines follow variable paths depending on time variation in the Earth’s magnetic field.

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The declination angle varies between -90° and +90°.

Currently, zero declination is occurring in some parts of Western Australia, and will likely move westward in coming years.

That said, it’s hard to predict exactly when an area will have zero declination. This is because the rate of change is slow and current models of the Earth’s magnetic field only cover a few years, and are updated at roughly five-year intervals.

At some locations, alignment between magnetic north and geographic north is very unlikely at any time, based on predictions.

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Locations on this 2019 map with a green contour line have zero declination. Lines along which declination is zero are called agonic lines.

The ever-changing magnetic poles

Most compasses point towards Earth’s north magnetic pole, which is usually in a different place to the north geographic pole. The location of the magnetic poles is constantly changing.

Earth’s magnetic poles exist because of its magnetic field, which is produced by electric currents in the liquid part of its core. This magnetic field is defined by intensity and two angles, inclination and declination.

The relationship between geographic location and declination is something people using magnetic compasses have to consider. Declination is the reason a compass reading for north in one location is different to a reading for north in another, especially if there is considerable distance between both locations.

Bush walkers have to be mindful of declination. In Perth, declination is currently close to 0° but in eastern Australia it can be up to 12°. This difference can be significant. If a bush walker following a magnetic compass disregards the local value of declination, they may walk in the wrong direction.

The polarity of Earth’s magnetic poles has also changed over time and has undergone pole reversals. This was significant as we learnt more about plate tectonics in the 1960s, because it linked the idea of seafloor spreading from mid-ocean ridges to magnetic pole reversals.

Geographic north

Geographic north, perhaps the more straightforward of the two, is the direction that points straight at the North Pole from any location on Earth.

When flying an aircraft from A to B, we use directions based on geographic north. This is because we have accurate geographic locations for places and need to follow precise routes between them, usually trying to minimise fuel use by taking the shortest route. All GPS navigation uses geographic location.

Geographic coordinates, latitude and longitude, are defined relative to Earth’s spheroidal shape. The geographic poles are at latitudes of 90°N (North Pole) and 90°S (South Pole), whereas the Equator is at 0°.

An alignment at Greenwich

For hundreds of years, declination at Greenwich was negative, meaning compass needles were pointing west of true north.

At the time of writing this article I used an online calculator to discover that, at the Greenwich Observatory, the Earth’s magnetic field currently has a declination just above zero, about +0.011°.

The average rate of change in the area is about 0.19° per year, which at Greenwich’s latitude represents about 20km per year. This means next year, locations about 20km west of Greenwich will have zero declination.

It’s impossible to say how long compasses at Greenwich will now point east of true north.

Regardless, an alignment after 360 years at the home of the Prime Meridian is undoubtedly a once-in-a-lifetime occurrence.

See the full article here .


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SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

With the right tools and careful insight, who knows what we might find.

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CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

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From University of New South Wales: “Cave secrets unlocked to show past drought and rainfall patterns”

U NSW bloc

From University of New South Wales

08 Jul 2019
Lachlan Gilbert

Global trends in cave waters identify how stalagmites reveal past rainfall and drought patterns.

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Stalagmites and stalactites in the Buchan Caves, Victoria, Australia. Picture: Shutterstock

A first-ever global analysis of cave drip waters has shown where stalagmites can provide vital clues towards understanding past rainfall patterns.

In a study published recently in the prestigious journal Nature Communications, UNSW Sydney scientists led an international group of researchers to amass the data of 163 drip sites in 39 caves on five continents.

They found that in climates that have a mean average temperature of less than 10oC, isotopes of oxygen in cave drip water were similarly composed as those measured in rainwater. As UNSW’s Dr Andy Baker explains, this follows what you would expect in colder climates with less evaporation of rainfall.

“This oxygen in the water drips from the stalactites and onto the stalagmites,” says Dr Baker, from UNSW’s School of Biological and Earth and Environmental Sciences.

“The drip water originally comes from rainfall, providing a direct link to the surface climate. Understanding the extent to which the oxygen isotopic composition of drip water is related to rainfall is a fundamental research question which will unlock the full climate potential of stalagmites and stalactites.”

But when the researchers examined the oxygen isotopes in drip waters in warmer areas, the oxygen isotopes in the drip waters corresponded to just some of the rain events, as revealed in the stalagmites. Dr Baker says that in such climates, evaporation not only reduces the amount of rainwater that eventually makes its way to the groundwater (a process known as rainfall recharge), but the oxygen isotopes themselves are changed by this process.

“In hotter climates, recharge to the subsurface doesn’t occur from all rain events, rather it likely only occurs after very heavy rain, or seasonally. This study identifies this for the first time and also provides a range of temperatures constraints – this was never known before,” he says.

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Dripping station at the Arcy-sur-Cure Cave (Yonne, Central-France). The dripping water is regularly sampled at this station and the modern calcite is gathered on a glass. Picture: D. Genty

In effect, he says, oxygen isotopes in stalagmites in warmer climates display the balance between wet weather events and prolonged periods of drying.

“For stalagmites in warm regions it suggests that the oxygen isotope composition will tell us about when recharge occurred – in other words, when, and how often,” Dr Baker says.

“And that is as valuable as it is unique. In regions like mainland Australia, with extreme weather events like drought and flooding rains, it’s a tool to see how often both occurred in the past.”

Dr Baker says that with this knowledge it will help us understand how important rainfall is in the replenishment of our groundwater resource.

“This knowledge will improve our understanding of how sustainable our use of groundwater is, especially in regions where groundwater is only recharged by rain,” he says.

See the full article here .


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U NSW Campus

Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

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From University of New South Wales: “1 in 2 people in NSW’s coastal community don’t think sea level rise will impact them directly”

U NSW bloc

From University of New South Wales

07 Jun 2019
Isabelle Dubach

50% of surveyed NSW coastal users don’t think that sea level rise will impact them, a report into the NSW community’s views on coastal hazards shows.

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Collaroy during the 2016 storm. Credit: UNSW’s Water Research Laboratory

Half of NSW’s coastal community thinks rising sea levels will not impact them directly, new data released today by UNSW scientists has shown – and 25% of surveyed accommodation businesses situated close to the coast are unsure if sea level rise is even occurring.

The report – released on the anniversary of the 2016 East Coast Low ‘superstorm’ that saw widespread damage along Australia’s east coast, including the collapse of a Collaroy swimming pool – describes what the NSW community understands about coastal erosion and inundation, as well as the driving forces behind these hazards: sea level rise and severe coastal storms.

“Our coastline is changing. Many locations along the NSW coast are seeing amenity loss and infrastructure damage associated with erosion and inundation – that is, the flooding of normally dry land by sea water, often caused by storms surges or king tides,” says Professor Rob Brander from the School of Biological, Earth and Environmental Sciences, who is also known as “Dr Rip”.

“These storm events will continue in the future. Combined with anticipated sea level rise, they’ll only enhance the extent and cost of coastal erosion damage and lead to greater inundation of coastal zones throughout NSW in the future, particularly in low-lying estuarine areas,” he says.

The researchers say people’s understanding and perception of storms and sea level rise, and their associated impacts of erosion and inundation, can significantly influence how and whether they engage in coastal adaptation actions – often influencing the success or failure of those actions.

“That’s why we wanted to find out what coastal communities understand and perceive about these hazards and how these hazards will affect their interactions with, and use of, the coast in the future,” says study author Anna Attard from UNSW Science.

“We think that’s an important aspect of building community resiliency and preparedness to coastal erosion and inundation.”

The My Coast NSW Study took place in 2017 and 2018, surveying more than 1000 people from all over the NSW coast, across three main groups: Coastal Management Professionals (i.e. government, academics, researchers and engineers), General Coastal Users (a cross section of people who use the NSW coast), and Coastal Accommodation Businesses (owners, managers or employees of accommodation businesses situated close to the coast).

The researchers say the resulting report provides an evidence-based information platform to help local governments and coastal management professionals in the future development of effective educational strategies and programs.

“Our ultimate goal is to help improve the ability of NSW coastal communities to adapt sustainably to the risk of coastal erosion and inundation,” Ms Attard says.

Lack of community knowledge about the direct impact of sea level rise is one of the key aspects of the report – which the authors say is concerning, given that sea level rise is a key factor driving coastal erosion and inundation.

“We found that only about 50% of general coastal users think that sea level rise will impact them directly – that’s a worry, given that estimates suggest that by 2100, sea level rise could increase by a metre or more if greenhouse gas emissions continue unchanged,” Ms Attard says.

“Even more worryingly, 25% of coastal accommodation businesses don’t know or are unsure if sea levels are even rising at all.”

The scientists say sea level rise will affect everybody, from those who use the coast day-to-day, to those who may visit a few times a year – and not just people on the front line living near the cost, either.

“Rising sea levels mean far-reaching impacts on people’s transport, infrastructure, sewerage and water, to name just a few examples,” Ms Attard says.

“It could also affect how you’re able to use your favourite beach, which you may only visit once a year.”

The researchers also explored how often people thought big storms like the 2016 East Coast low event were occurring.

“45% of the general coastal users we surveyed think storms like the one in 2016 occur only every 20 years, so they think it’s rarer than what’s actually happening. But over the last decade or so, we’ve actually had a few major storms in NSW – in 2016, 2015 and 2007, at least,” Ms Attard says.

The report also found a clear disconnect between what coastal management professionals think the public should know about coastal hazards, and what the public flagged as wanting to know more about.

“General coastal users told us that would like to know more about how climate change will impact their immediate coast, what the possible solutions are and who the ‘key players’ of coastal management are,” says Ms Attard.

“But coastal professionals said that coastal communities need more information about direct personal and public risks associated with coastal hazards, general information about coastal hazards and processes, and their impacts on the greater NSW community – that’s very different from what the general users said their information needs are.

“Community engagement needs to be a two-way process to address that disconnect.”

The My Coast study was funded under the joint State and Commonwealth Natural Disaster Resilience Program. The grant was awarded to UNSW in March 2017 and the study was conducted in partnership with the Sydney Coastal Councils Group (SCCG), Surf Life Saving NSW (SLS NSW) and the NSW Government Office of Environment and Heritage (OEH).

The full My Coast study report, along with multiple fact sheets and a guide for teachers, can be accessed online.

See the full article here .


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U NSW Campus

Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

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From University of New South Wales: “Quantum scientists demonstrate world-first 3D atomic-scale quantum chip architecture”

U NSW bloc

From University of New South Wales

08 Jan 2019
Isabelle Dubach

UNSW scientists have shown that their pioneering single atom technology can be adapted to building 3D silicon quantum chips – with precise interlayer alignment and highly accurate measurement of spin states. The 3D architecture is considered a major step in the development of a blueprint to build a large-scale quantum computer.

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Study authors Dr Joris Keizer and Professor Michelle Simmons

UNSW researchers at the Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) have shown for the first time that they can build atomic precision qubits in a 3D device – another major step towards a universal quantum computer.

The researchers, led by 2018 Australian of the Year and Director of CQC2T Professor Michelle Simmons, have demonstrated that they can extend their atomic qubit fabrication technique to multiple layers of a silicon crystal – achieving a critical component of the 3D chip architecture that they introduced to the world in 2015. This new research is published today in Nature Nanotechnology.

The group is the first to demonstrate the feasibility of an architecture that uses atomic-scale qubits aligned to control lines – which are essentially very narrow wires – inside a 3D design.

What’s more, team members were able to align the different layers in their 3D device with nanometer precision – and showed they could read out qubit states with what’s called ‘single shot’, i.e. within one single measurement, with very high fidelity.

“This 3D device architecture is a significant advancement for atomic qubits in silicon,” says Professor Simmons.

“To be able to constantly correct for errors in quantum calculations – an important milestone in our field – you have to be able to control many qubits in parallel.

“The only way to do this is to use a 3D architecture, so in 2015 we developed and patented a vertical crisscross architecture. However, there were still a series of challenges related to the fabrication of this multi-layered device. With this result we have now shown that engineering our approach in 3D is possible in the way we envisioned it a few years ago.”

In this paper, the team has demonstrated how to build a second control plane or layer on top of the first layer of qubits.

“It’s a highly complicated process, but in very simple terms, we built the first plane, and then optimised a technique to grow the second layer without impacting the structures in first layer,” explains CQC2T researcher and co-author, Dr Joris Keizer.

“In the past, critics would say that that’s not possible because the surface of the second layer gets very rough, and you wouldn’t be able to use our precision technique anymore – however, in this paper, we have shown that we can do it, contrary to expectations.”

The team members also demonstrated that they can then align these multiple layers with nanometer precision.

“If you write something on the first silicon layer and then put a silicon layer on top, you still need to identify your location to align components on both layers. We have shown a technique that can achieve alignment within under five nanometers, which is quite extraordinary,” Dr Keizer says.

Lastly, the researchers were able to measure the qubit output of the 3D device single shot – i.e. with a single, accurate measurement, rather than having to rely on averaging out millions of experiments.

“This will further help us scale up faster,” Dr Keizer explains.

Towards commercialisation

Professor Simmons says that this research is a milestone in the field.

“We are working systematically towards a large-scale architecture that will lead us to the eventual commercialisation of the technology.

“This is an important development in the field of quantum computing, but it’s also quite exciting for SQC,” says Professor Simmons, who is also the founder and a director of SQC.

Since May 2017, Australia’s first quantum computing company, Silicon Quantum Computing Pty Limited (SQC), has been working to create and commercialise a quantum computer based on a suite of intellectual property developed at CQC2T and its own proprietary intellectual property.

“While we are still at least a decade away from a large-scale quantum computer, the work of CQC2T remains at the forefront of innovation in this space. Concrete results such as these reaffirm our strong position internationally,” she concludes.

See the full article here .


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Please help promote STEM in your local schools.

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U NSW Campus

Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

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From University of New South Wales: “Harnessing the power of ‘spin-orbit’ coupling: scaling up spin-based quantum computation”

U NSW bloc

From University of New South Wales

10 Dec 2018
Karen Viner-Smith

Research teams from UNSW are investigating multiple pathways to scale up atom-based computing architectures using spin-orbit coupling – advancing towards their goal of building a silicon-based quantum computer in Australia.

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Artist’s impression of spin-orbit coupling of atom qubits. Illustration: Tony Melov. Credit: CQC2T

Australian scientists have investigated new directions to scale up qubits utilising their spin-orbit coupling, adding a new suite of tools to the armory.

Spin-orbit coupling, the coupling of the qubits’ orbital and spin degree of freedom, allows the manipulation of the qubit via electric, rather than magnetic fields. Using the electric dipole coupling between qubits means they can be placed further apart, thereby providing flexibility in the chip fabrication process.

In one of these approaches, published in Science Advances, a team of scientists led by UNSW Professor Sven Rogge investigated the spin-orbit coupling of a boron atom in silicon.

“Single boron atoms in silicon are a relatively unexplored quantum system, but our research has shown that spin-orbit coupling provides many advantages for scaling up to a large number of qubits in quantum computing,” says Professor Rogge, Program Manager at the Centre for Quantum Computation and Communication Technology (CQC2T).

Following on from earlier results from the UNSW team, published last month in Physical Review X, Rogge’s group has now focused on applying fast read-out of the spin state (1 or 0) of just two boron atoms in an extremely compact circuit all hosted in a commercial transistor.

“Boron atoms in silicon couple efficiently to electric fields, enabling rapid qubit manipulation and qubit coupling over large distances. The electrical interaction also allows coupling to other quantum systems, opening up the prospects of hybrid quantum systems,” says Rogge.

Phosphorus atom qubits

Another piece of recent research by Prof Michelle Simmons’ team at UNSW has also highlighted the role of spin orbit coupling in atom-based qubits in silicon, this time with phosphorus atom qubits. The research was recently published in npj Quantum Information.

The research revealed surprising results. For electrons in silicon — and in particular those bound to phosphorus donor qubits — spin orbit control was commonly regarded as weak, giving rise to seconds long spin lifetimes. However, the latest results revealed a previously unknown coupling of the electron spin to the electric fields typically found in device architectures created by control electrodes.

“By careful alignment of the external magnetic field with the electric fields in an atomically engineered device, we found a means to extend these spin lifetimes to minutes,” says Professor Michelle Simmons, Director, CQC2T.

“Given the long spin coherence times and the technological benefits of silicon, this newly discovered coupling of the donor spin with electric fields provides a pathway for electrically-driven spin resonance techniques, promising high qubit selectivity,” says Simmons.

Both results highlight the benefits of understanding and controlling spin orbit coupling for large-scale quantum computing architectures.

Commercialising silicon quantum computing IP in Australia

Since May 2017, Australia’s first quantum computing company, Silicon Quantum Computing Pty Limited (SQC), has been working to create and commercialise a quantum computer based on a suite of intellectual property developed at the Australian Centre of Excellence for Quantum Computation and Communication Technology (CQC2T). Its goal is to produce a 10-qubit prototype device in silicon by 2022 as the forerunner to a commercial scale silicon-based quantum computer.

As well as developing its own proprietary technology and intellectual property, SQC will continue to work with CQC2T and other participants in the Australian and International Quantum Computing ecosystems, to build and develop a silicon quantum computing industry in Australia and, ultimately, to bring its products and services to global markets.

See the full article here .


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Please help promote STEM in your local schools.

Stem Education Coalition

U NSW Campus

Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

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From University of New South Wales: ” In search of the best telescope location, UNSW astronomer and alumnus head to high places”

U NSW bloc

From University of New South Wales

21 Aug 2018
Ivy Shih

An international effort to pinpoint the site for a new telescope is relying on technology developed by a UNSW alumnus during his PhD.

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Dr Colin Bonner (left) and Professor Michael Ashley on location at Ali Observatory. Photo: Colin Bonner

It is a tale of North and South with an astronomical twist, with a UNSW astronomer and a UNSW PhD alumnus heading from Antarctica to the Tibetan Plateau to help find the best site for a new, 12-metre optical telescope.

This year, Professor Michael Ashley from the School of Physics and alumnus Dr Colin Bonner travelled to Ali Observatory in western Tibet to lead the testing and installation of SODAR (Sound Detection and Ranging), a device the astronomers will use to decide where a new telescope is best located.

Ali Observatory on the Tibetan Plateau over 5100 metres above sea level

The road to Tibet was a journey from one extreme to another. Before Tibet, Professor Ashley and Dr Bonner had been on scientific expeditions deploying telescopes in some of the most remote locations of Antartica, including the South Pole itself at latitude 90S. To reach Ali Observatory, the pair had to travel from Tibet’s capital Lhasa to Nagari Gunsa airport, the fourth highest altitude airport in the world.

Ali Observatory is situated on the Tibetan Plateau, at more than 5100 metres above sea level. It’s a good location for studying the night sky, due to the combination of its high altitude and predominantly dry seasonal conditions in the region.

“In astronomy you want to be as high as you can be because it gets you above some of the atmosphere, where it is nice and cold and there is not much water vapour,” says Professor Ashley.

“It’s an amazing location. Antarctica is amazing in more ways than one, but the Tibetan Plateau is like the surface of the moon, albeit with some tufts of hardy grass and a few yaks.”

The pair limited their time at Ali Observatory to a few hours at a time, however, to reduce the risk of altitude sickness.

“The photos don’t capture the feeling of being there – you really notice the difficulty of breathing,” says Professor Ashley.

Ashley and Bonner travelled to Tibet to install a SODAR to help evaluate the stability of the atmosphere at the location.

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Fulcrum 3D’s sonar radar (cone-shaped object in the centre) installed onsite at Ali Observatory. Photo: Colin Bonner

Atmosphere stability is critical for astronomers: tens of metres difference between where a telescope is placed can make the difference between a blurry image of a star and a clear high-resolution one.

Original versions of the SODAR were put through their paces in Antarctica, where Professor Ashley and Dr Bonner previously worked at an international observatory.

Chinese astronomer collaborators onsite in Antarctica saw the SODAR’s effectiveness and called on the combined expertise of Professor Ashley and Dr Bonner to apply it at Ali Observatory.

There are now plans to construct a 12-metre optical telescope in Tibet. This will be the latest addition to an international cluster of smaller telescopes from the United States and Japan.

“A big part of the visit was assessing locations – there is no point in having a Ferrari-style telescope put on a site that would not produce optimal conditions for astronomers,” says Dr Bonner.

“If you are going to put in money to build a telescope, you need to be absolutely sure it is the best location.”

The device will remain at Ali Observatory for at least a couple of years to collect seasonal atmospheric data. The information will then be analysed by Fulcrum3D and astronomers at the National Astronomical Observatory of China and UNSW to determine the best location for the new telescope.

See the full article here .


five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

U NSW Campus

Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

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From University of New South Wales: “Seeing is believing – precision atom qubits achieve major milestone”

U NSW bloc

University of New South Wales

07 Mar 2018
Deborah Smith

The unique Australian approach of creating quantum bits from precisely positioned individual atoms in silicon is reaping major rewards, with two of these atom qubits made to “talk” to each other for the first time.

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Scientia Professor Michelle Simmons with a scanning tunnelling microscope. Credit: UNSW

The unique Australian approach of creating quantum bits from precisely positioned individual atoms in silicon is reaping major rewards, with UNSW Sydney-led scientists showing for the first time that they can make two of these atom qubits “talk” to each other.

The team – led by UNSW Scientia Professor Michelle Simmons, Director of the Centre of Excellence for Quantum Computation and Communication Technology, or CQC2T – is the only group in the world that has the ability to see the exact position of their qubits in the solid state.

Simmons’ team create the atom qubits by precisely positioning and encapsulating individual phosphorus atoms within a silicon chip. Information is stored on the quantum spin of a single phosphorus electron.

The team’s latest advance – the first observation of controllable interactions between two of these qubits – is published in the journal Nature Communications. It follows two other recent breakthroughs using this unique approach to building a quantum computer.

By optimising their nano-manufacturing process, Simmons’ team has also recently created quantum circuitry with the lowest recorded electrical noise of any semiconductor device.

And they have created an electron spin qubit with the longest lifetime ever reported in a nano-electric device – 30 seconds.

“The combined results from these three research papers confirm the extremely promising prospects for building multi-qubit systems using our atom qubits,” says Simmons.

2018 Australian of the Year inspired by Richard Feynman

Simmons, who was named 2018 Australian of the Year in January for her pioneering quantum computing research, says her team’s ground-breaking work is inspired by the late physicist Richard Feynman.

“Feynman said: ‘What I cannot create, I do not understand’. We are enacting that strategy systematically, from the ground up, atom by atom,” says Simmons.

“In placing our phosphorus atoms in the silicon to make a qubit, we have demonstrated that we can use a scanning probe to directly measure the atom’s wave function, which tells us its exact physical location in the chip. We are the only group in the world who can actually see where our qubits are.

“Our competitive advantage is that we can put our high-quality qubit where we want it in the chip, see what we’ve made, and then measure how it behaves. We can add another qubit nearby and see how the two wave functions interact. And then we can start to generate replicas of the devices we have created,” she says.

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A scanning tunnelling microscope image showing the electron wave function of a qubit made from a phosphorus atom precisely positioned in silicon. Credit: UNSW

For the new study, the team placed two qubits – one made of two phosphorus atoms and one made of a single phosphorus atom – 16 nanometres apart in a silicon chip.

“Using electrodes that were patterned onto the chip with similar precision techniques, we were able to control the interactions between these two neighbouring qubits, so the quantum spins of their electrons became correlated,” says study lead co-author, Dr Matthew Broome, formerly of UNSW and now at the University of Copenhagen.

“It was fascinating to watch. When the spin of one electron is pointing up, the other points down, and vice versa.

“This is a major milestone for the technology. These type of spin correlations are the precursor to the entangled states that are necessary for a quantum computer to function and carry out complex calculations,” he says.

Study lead co-author, UNSW’s Sam Gorman, says: “Theory had predicted the two qubits would need to be placed 20 nanometres apart to see this correlation effect. But we found it occurs at only 16 nanometres apart.

“In our quantum world, this is a very big difference,” he says. “It is also brilliant, as an experimentalist, to be challenging the theory.”


UNSW Sydney-led scientists have shown for the first time that they can make two precisely placed phosphorous atom qubits “talk” to each other.

Leading the race to build a quantum computer in silicon

UNSW scientists and engineers at CQC2T are leading the world in the race to build a quantum computer in silicon. They are developing parallel patented approaches using single atom and quantum dot qubits.

“Our hope is that both approaches will work well. That would be terrific for Australia,” says Simmons.

The UNSW team have chosen to work in silicon because it is among the most stable and easily manufactured environments in which to host qubits, and its long history of use in the conventional computer industry means there is a vast body of knowledge about this material.

In 2012, Simmons’ team, who use scanning tunnelling microscopes to position the individual phosphorus atoms in silicon and then molecular beam epitaxy to encapsulate them, created the world’s narrowest conducting wires, just four phosphorus atoms across and one atom high.

In a recent paper published in the journal Nano Letters, they used similar atomic scale control techniques to produce circuitry about 2-10 nanometres wide and showed it had the lowest recorded electrical noise of any semiconductor circuitry. This work was undertaken jointly with Saquib Shamim and Arindam Ghosh of the Indian Institute of Science.

“It’s widely accepted that electrical noise from the circuitry that controls the qubits will be a critical factor in limiting their performance,” says Simmons.

“Our results confirm that silicon is an optimal choice, because its use avoids the problem most other devices face of having a mix of different materials, including dielectrics and surface metals, that can be the source of, and amplify, electrical noise.

“With our precision approach we’ve achieved what we believe is the lowest electrical noise level possible for an electronic nano-device in silicon – three orders of magnitude lower than even using carbon nanotubes,” she says.

In another recent paper in Science Advances, Simmons’ team showed their precision qubits in silicon could be engineered so the electron spin had a record lifetime of 30 seconds – up to 16 times longer than previously reported. The first author, Dr Thomas Watson, was at UNSW undertaking his PhD and is now at Delft University of Technology.

“This is a hot topic of research,” says Simmons. “The lifetime of the electron spin – before it starts to decay, for example, from spin up to spin down – is vital. The longer the lifetime, the longer we can store information in its quantum state.”

In the same paper, they showed that these long lifetimes allowed them to read out the electron spins of two qubits in sequence with an accuracy of 99.8 percent for each, which is the level required for practical error correction in a quantum processor.

Australia’s first quantum computing company

Instead of performing calculations one after another, like a conventional computer, a quantum computer would work in parallel and be able to look at all the possible outcomes at the same time. It would be able to solve problems in minutes that would otherwise take thousands of years.

Last year, Australia’s first quantum computing company – backed by a unique consortium of governments, industry and universities – was established to commercialise CQC2T’s world-leading research.

Operating out of new laboratories at UNSW, Silicon Quantum Computing Pty Ltd has the target of producing a 10-qubit demonstration device in silicon by 2022, as the forerunner to a silicon-based quantum computer.

The Australian government has invested $26 million in the $83 million venture through its National Innovation and Science Agenda, with an additional $25 million coming from UNSW, $14 million from the Commonwealth Bank of Australia, $10 million from Telstra and $8.7 million from the NSW Government.

It is estimated that industries comprising approximately 40% of Australia’s current economy could be significantly impacted by quantum computing. Possible applications include software design, machine learning, scheduling and logistical planning, financial analysis, stock market modelling, software and hardware verification, climate modelling, rapid drug design and testing, and early disease detection and prevention.

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