Terahertz radiation from CdxHg1-xTe photoexcited by femtosecond laser pulses

Terahertz radiation from CdxHg1-xTe samples excited by femtosecond Ti:sapphire laser pulses were measured by using an ultrafast photoconductive antenna manufactured from low-temperature grown GaAs. Terahertz fields radiated by the samples of all three investigated alloy compositions with x=0, 0.2, and 0.3 were of the same order of magnitude. No azimuthal angle dependence of the radiated signal was detected, which evidences that linear current surge effect is dominating over nonlinear optical rectification. (C) 2004 American Institute of Physics.