Polarization independent and optical-controlled metamaterial modulator in terahertz regime

Reconfigurable metamaterials for terahertz wave manipulation

“…As a result, the intensity of terahertz waves at the SRR resonance frequency was decreased from 95% to 65% by increasing the pump optical power from 0 to 10 mW at an optical wavelength of 800 nm. Following this study, numerous implementations of optically controlled metamaterials with different unit-cell configurations [34][35][36][37][38][39][40] and photo-absorbing substrates [37,[41][42][43] were investigated for terahertz intensity modulation with improved modulation depth, modulation bandwidth, modulation speed, and polarization insensitivity.…”

“…Modulation speeds as fast as 20 ps have been achieved by the use of ErAs/GaAs superlattice substrates at an optical wavelength of 800 nm [42]. Moreover, to obtain polarization-insensitive terahertz intensity modulation, several reconfigurable metamaterials with symmetric unit-cell geometries have been developed [38][39][40]. It should be noted that most of the demonstrated optically controlled reconfigurable metamaterials utilized for terahertz intensity modulation have been restricted to operate at narrow frequency bands due to their resonant nature.…”