In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 37, No. 6R ( 1998-06-01), p. 3210-
Abstract:
By using an improved method of two-wavelength excited photoluminescence,
we observed a considerable decrease in the band-to-band photoluminescence intensity of an undoped GaAs/AlGaAs quantum well structure when a below-gap excitation was superposed on an above-gap excitation.
This intensity quenching was attributed to the enhanced nonradiative recombination through below-gap states which were activated by the below-gap
excitation. By changing the energy of above-gap excitation, it was shown that these
below-gap states were formed neither inside GaAs well layers nor at the GaAs/AlGaAs heterointerface, but inside AlGaAs barrier layers.
Tuning the photon energy of below-gap excitation revealed that the activation energy of the nonradiative recombination process via these below-gap states is
around 1.2 eV. Lowering the above-gap excitation density to a single-photon-counting
region enabled us to characterize below-gap states spectroscopically without the need of a high-power tunable laser source for the below-gap excitation.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.37.3210
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1998
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7