%0 Journal Article %J Applied Physics Letters %D 1996 %T Interband impact ionization by terahertz illumination of InAs heterostructures %A Markelz, A. G. %A Asmar, N. G. %A Brar, B. %A Gwinn, E. G. %K energy %K far-infrared excitation %K inas/alsb quantum-wells %K inplane %K modulation %K Physics %X

Experimental studies of InAs heterostructures illuminated by far-infrared (FIR) radiation reveal an abrupt increase in the charge density for FIR intensities above a threshold value that rises with increasing frequency. We attribute this charge density rise to interband impact ionization in a regime in which omega tau(m) similar to 1, where tau(m) is the momentum relaxation time, and f=omega/2 pi is the FIR frequency. The dependence of the density rise on the FIR field strength supports this interpretation, and gives threshold fields of 3.7-8.9 kV/cm for the frequency range 0.3-0.66 THz. (C) 1996 American Institute of Physics.

%B Applied Physics Letters %V 69 %P 3975-3977 %8 Dec %@ 0003-6951 %G English %9 Article %M WOS:A1996VY89400005 %! Appl. Phys. Lett.Appl. Phys. Lett. %R 10.1063/1.117842 %0 Conference Proceedings %B Proceedings of the International Conference on the Physics of Semiconductors %D 1994 %T Frequency Dependence of the Third Order Susceptibility of InAs Quantum Wells at Terahertz Frequencies %A Markelz, A.G. %A Cerne, J. %A Gwinn, E. G. %A Brar, B. %A Kroemer, H. %B Proceedings of the International Conference on the Physics of Semiconductors %P 1193-1196 %8 08/1994 %G eng