From Berkeley Lab: “Berkeley Lab Researchers Use Metamaterials to Observe Giant Photonic Spin Hall Effect”
March 21, 2013
“Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have once again demonstrated the incredible capabilities of metamaterials – artificial nanoconstructs whose optical properties arise from their physical structure rather than their chemical composition. Engineering a unique two-dimensional sheet of gold nanoantennas, the researchers were able to obtain the strongest signal yet of the photonic spin Hall effect, an optical phenomenon of quantum mechanics that could play a prominent role in the future of computing.
Light propagating through a metamaterial follows a curved trajectory that drags light with different circular polarization in opposite transverse directions to produce a giant photonic Spin Hall effect.
‘With metamaterial, we were able to greatly enhance a naturally weak effect to the point where it was directly observable with simple detection techniques,’ said Xiang Zhang, a faculty scientist with Berkeley Lab’s Materials Sciences Division who led this research. ‘We also demonstrated that metamaterials not only allow us to control the propagation of light but also allows control of circular polarization. This could have profound consequences for information encoding and processing.’
Zhang is the corresponding author of a paper describing this work in the journal Science. The paper is titled Photonic Spin Hall Effect at Metasurfaces. Co-authors are Xiaobo Yin, Ziliang Ye, Jun Sun Rho and Yuan Wang.
Metamaterials have garnered a lot of attention in recent years because their unique structure affords electromagnetic properties unattainable in nature. For example, a metamaterial can have a negative index of refraction, the ability to bend light backwards, unlike all materials found in nature, which bend light forward. Zhang, who holds the Ernest S. Kuh Endowed Chair Professor of Mechanical Engineering at the University of California (UC) Berkeley, where he also directs the National Science Foundation’s Nano-scale Science and Engineering Center, has been at the forefront of metamaterials research.
See the full article here.
A U.S. Department of Energy National Laboratory Operated by the University of California
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