Effect of neutral donor scattering on the time-dependent exciton-polariton photoluminescence line shape in GaAs
Abstract
The importance of neutral donor scattering on the observed time-resolved exciton-polariton line shape in GaAs at low temperatures is demonstrated. Samples which in continuous excitation luminescence show a single polariton peak can have substantially different line shapes at short delay times after excitation with mode-locked laser pulses. A series of time-resolved spectra show at short delays after the laser pulses a doublet line shape which gradually transforms into a singlet with longer delays. We have explained this phenomenon as arising from the delay in arrival at the sample surface of polaritons in the energy region corresponding to the central ``dip'' due to neutral donor scattering. A time-dependent Boltzmann-equation model of polariton transport in the crystal incorporating only elastic neutral donor scattering has been constructed to simulate the experimental results.
- Publication:
-
Physical Review B
- Pub Date:
- July 1986
- DOI:
- 10.1103/PhysRevB.34.1006
- Bibcode:
- 1986PhRvB..34.1006S
- Keywords:
-
- 71.36.+c;
- 78.55.-m;
- Polaritons;
- Photoluminescence properties and materials