UV emission from left-handed material through second harmonic generation: optical nanoantenna and imaging application

In this Letter, the authors present a new design of left-handed material structure that can emit UV light via second harmonic generation. It has been shown that negative index can be achieved by excitation of surface polariton waves operating in dispersion regime with anti-parallel refracted wave vector and the Poynting vector. Coupled dipole approximation predicts negative real values of both permeability μ and permittivity ε with extremely low imaginary values at visible/UV light. Through 3D FDTD numerical simulations, far-field spectrum and high transmission efficiency >;98% can be attained, resulting to high directionality, which favours its potential application as a plasmonic nanoantenna. Influence of structural parameters on transmission and dispersion properties is also investigated in detail that might be useful for imaging applications.