Terahertz emission from a GaAs/AlAs coupled multilayer cavity with nonlinear optical susceptibility inversion

Abstract

Terahertz wave generation was demonstrated by the difference frequency generation of two cavity modes in a polarization-controlled GaAs/AlAs coupled multilayer cavity. Inversion of the second-order nonlinear optical susceptibility was achieved by face-to-face bonding of the two halves of a coupled cavity structure grown on a (113)B-oriented GaAs substrate. Signal enhancement due to this inversion was observed through the comparison of inverted and normal coupled cavity samples in both simulated and experimentally observed terahertz waveforms produced by simultaneous excitation of two cavity modes using femtosecond laser pulses.