Journal of Vacuum Science & Technology B, Vol.12, No.2, 1150-1152, 1994
Exciton Dynamics in Multiquantum-Well CdTe-Cd1-xMnxTe Systems
The exciton dynamics associated with the transfer of energy from the light-hole state to both the heavy-hole state and to a donor bound exciton (D0X) are investigated utilizing time-resolved spectroscopy, in a multiquantum well sample of CdTe-Cd1-xMnxTe containing 75 angstrom wells and 150 angstrom barriers. The results show that the relaxation time of the light-hole to the heavy-hole state occurs, at low temperature, in a time less-than-or-equal-to 40 ps whereas the combined drift/diffusion of the excitons in the plane of the quantum well and their subsequent trapping at donor states occurs in a time approximately 80 ps. Theoretical calculations show that the light-hole-heavy-hole carrier relaxation time is consistent with confined (acoustic) phonon relaxation and that the equivalent in-plane mobility is consistent with interface roughness scattering.
Keywords:INTERFACE-ROUGHNESS;QUANTUM WELLS