Intraband relaxation time in wurtzite InGaN/GaN quantum-well structures with (10(1)over-bar0) crystal orientation

Intraband relaxation time is investigated theoretically for a wurtzite InGaN/GaN quantum well (QW) with a (10 (1) over bar0) crystal orientation. The results are compared with those of (0001)-oriented QW structures. It is found that the linewidths for the h-h scattering of the (10 (1) over bar0)-oriented QW is largely reduced compared to that of the (0001)-oriented QW. This is because the hole effective mass of the (10 (1) over bar0)-oriented QW is reduced due to the inclusion of the anisotropic strain in the QW plane. In the case of the (0001)-oriented QW, considering only the h-h scattering near subband edges is a good approximation. On the other hand, in the case of the (10 (1) over bar0)-oriented QW, linewidths for the e-e and e-h scatterings are comparable to that for the h-h scattering. The intraband relaxation times near band edges for (0001)- and (10 (1) over bar0)-oriented QWs are about 20 and 25 fs at a sheet carrier density of 2x10(12) cm(-2), respectively. These values are shorter than those (40-100 fs) reported for InP and GaAs. (C) 2002 American Institute of Physics.