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All-angle negative refraction and active flat lensing of ultraviolet light



Ting Xu, Amit Agrawal, Maxim Abashin, Kenneth J. Chau, Henri Lezec


The ability of a left-handed medium to sustain backwards electromagnetic waves leads to counter-intuitive phenomena such as negative refraction. We report the experimental implementation of a three-dimensional negative-index metamaterial operating at an ultraviolet wavelength of 364nm. The metamaterial, based upon the concept of stacked coupled plasmonic waveguides, is fabricated using alternating layers of Ag and TiO2 and designed to have a quasi-isotropic refractive index close to -1, for both phase and power flow, represents a key step towards implementing the yet-unrealized three-dimensional free-space flat lens or Pendry-Veselago superlens.


Xu, T. , Agrawal, A. , abashin, M. , Chau, K. and Lezec, H. (2013), All-angle negative refraction and active flat lensing of ultraviolet light, Nature, [online], (Accessed April 23, 2024)
Created May 21, 2013, Updated October 12, 2021