Terahertz radiation from CdxHg1-xTe photoexcited by femtosecond laser pulses

Abstract

Terahertz radiation from CdxHg1-x,Te samples excited by femtosecond pulses generated by Ti:sapphire laser was measured by using an ultrafast photoconductive antenna. The radiated terahertz field magnitude was nearly the same for all three investigated alloy compositions with x = 0, 0.2 and 0.3. No azimuthal angle dependence of the radiated signal was detected, which evidences that a linear current surge effect is dominating over nonlinear optical rectification. Experimental observations are discussed in terms of the energy band structure of the investigated compound semiconductors. (c) 2004 Elsevier B.V. All rights reserved.