%0 Journal Article %J Semiconductor Science and Technology %D 1994 %T SUBCUBIC POWER DEPENDENCE OF 3RD-HARMONIC GENERATION FOR INPLANE, FAR-INFRARED EXCITATION OF INAS QUANTUM-WELLS %A Markelz, A. G. %A Asmar, N. G. %A Gwinn, E. G. %A Sherwin, M. S. %A Nguyen, C. %A Kroemer, H. %X

Large third-order, free-carrier nonlinear susceptibilities, chi(3) (to approximately 0.2 esu), and subcubic dependence of the third-harmonic power on the incident intensity, have been observed between 19 cm-1 and 23 cm-1 for InAs/AlSb quantum wells with electron sheet densities between 2.5 x 10(12) cm-2 and 8 X 10(12) cm-2. We find that the transmission of the fundamental, and the samples' DC conductivity, decrease with increasing incident intensity, indicating a large rise in the scattering rate. Using the intensity-dependent transmission to account for absorption in the sample is not sufficient to recover a cubic power law for the third-harmonic intensity. In addition, given the increased scattering rate indicated by the conductivity data, the bulk free-carrier chi(3) due to non-parabolicity should decrease dramatically with increasing fundamental intensity, contrary to our results. Thus, non-parabolicity alone cannot account for the observed third-harmonic response.

%B Semiconductor Science and Technology %V 9 %P 634-637 %8 May %@ 0268-1242 %G eng %M WOS:A1994NM75300063 %! Semicond. Sci. Technol. %R https://doi.org/10.1088/0268-1242/9/5S/063