We show examples of recent spectroscopic studies of CdTe/(Cd, Mn)Te and ZnSe/(Zn, Mn)Se multiquantum wells (MQWs). These strained-layer structures are sources of intense excitonic luminescence at low temperatures. Dependence of luminescence spectra on temperature and the especially pronounced influence of an external magnetic field are strong evidence that the emission is dominated by localized excitons which particularly for the (111) oriented CdTe/(Cd, Mn)Te MQWs are attached to the heterointerfaces. For the (100) ZnSe/(Zn, Mn)SeMQWs the luminescence amplitude typically decreases rapidly with temperature from 2 to 100 K indicating only a weakly localized exciton. Picosecond time-resolved experiments have yielded a direct measurement of exciton energy-loss rates and lifetimes which are found to depend on quantum well width, magnetic field, and on temperature.
Bibliographical noteFunding Information:
This work was supported by ONR contract N00014-83-K0653 and DOE grant DE-FG02-84ER45067 at Brown University, by ONR contract N00014-82-K0563 and AFOSR grant x3-0237 at Purdue University.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry