%0 Journal Article %J Applied Physics Letters %D 2006 %T Terahertz transmission characteristics of high-mobility GaAs and InAs two-dimensional-electron-gas systems %A Kabir, N. A. %A Yoon, Y. %A Knab, J. R. %A Chen, J. Y. %A Markelz, A. G. %A Reno, J. L. %A Sadofyev, Y. %A Johnson, S. %A Zhang, Y. H. %A Bird, J. P. %K field-effect transistors %K photoconductivity %K Physics %K plasma-waves %K radiation %K resonant detection %K subterahertz %X

Frequency-dependent complex conductivity of high-mobility GaAs and InAs two-dimensional-electron-gas (2DEG) systems is studied by terahertz time domain spectroscopy. Determining the momentum relaxation time from a Drude model, the authors find a lower value than that from dc measurements, particularly at high frequencies/low temperatures. These deviations are consistent with the ratio tau(t)/tau(q,) where tau(q) is the full scattering time. This suggests that small-angle scattering leads to weaker heating of 2DEGs at low temperatures than expected from dc mobilit9y. (c) 2006 American Institute of Physics.

%B Applied Physics Letters %V 89 %P 3 %8 Sep %@ 0003-6951 %G English %9 Article %M WOS:000240875800066 %] 132109 %! Appl. Phys. Lett.Appl. Phys. Lett. %R 10.1063/1.2357605