Dresden 2017 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 84: Heterostructures and Interfaces

HL 84.1: Talk

Friday, March 24, 2017, 09:30–09:45, POT 151

Recombination dynamics of excitons in (Ga,In)As/Ga(As,Sb) type-II heterostructures — •Sebastian Gies, Benjamin Holz, Christian Fuchs, Wolfgang Stolz, and Wolfram Heimbrodt — Department of Physics and Materials Science Center, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany

(Ga,In)As/Ga(As,Sb) heterostructures are a material system widely used as an active medium in IR-lasers. It is necessary to have profound knowledge about the basic relaxation and recombination processes to improve this material. We present a thorough study of these properties by continuous-wave (cw-) and time-resolved (TR-) photoluminescence spectroscopy (PL) at various temperatures. Therefore, we investigate (Ga,In)As/GaAs/Ga(As,Sb) type-II structures with GaAs interlayers of different thicknesses to modify the type-II transition. Upon changing temperature a complex interplay of relaxation, tunneling and thermal reactivation is found, that changes the PL spectra drastically. Furthermore, the TRPL reveals, that the relaxation of holes has a tremendous influence on the transients of the type-II PL. A rate-equation model is developed to quantify the relaxation.