Modulation of Negative Index Metamaterials in the Near-IR Range

TL;DR

This paper demonstrates optical modulation of negative index metamaterials in the near-infrared range using a Ag/Si/Ag structure, revealing fast dynamics driven by photoexcitation of silicon.

Contribution

It introduces a method to modulate the negative refractive index of fishnet metamaterials via optical excitation of silicon in the near-IR range.

Findings

Successful modulation of negative index in near-IR range

Fast dynamic response observed via pump-probe measurements

Silicon photoexcitation alters optical properties leading to index change

Abstract

Optical modulation of the effective refractive properties of a "fishnet" metamaterial with a Ag/Si/Ag heterostructure is demonstrated in the near-IR range and the associated fast dynamics of negative refractive index is studied by pump-probe method. Photo excitation of the amorphous Si layer at visible wavelength and corresponding modification of its optical parameters is found to be responsible for the observed modulation of negative refractive index in near-IR.