Bright and dark triplet states of the negatively charged magnetoexcitons revealed in photoluminescence and time-resolved measurements
Continuous and time-resolved magnetophotoluminescence measurements of three GaAs/Al{sub x}Ga{sub 1-x}As heterostructures have been made in high magnetic fields. The spectra revealed the presence of a singlet and two triplet states (the so-called ''bright'' and ''dark'' states) of the negatively charged magnetoexciton, in addition to the neutral exciton. For an asymmetrically doped single quantum well sample, the singlet and the dark triplet states converge (and possibly cross) at a field of about 40 T. The two single heterojunction samples on the other hand show no such convergence, and the singlet remains the fundamental state at least in fields to 60 T. The lifetimes of the charged magnetoexcitons increased linearly with field, whereas the neutral exciton was essentially field independent. The results clarify earlier experimental studies, and provide a confirmation of a recent theory of the behavior of charged magnetoexcitons in magnetic fields by Wojs [Phys Rev. B 62, 4630 (2000)].
- Sponsoring Organization:
- (US)
- OSTI ID:
- 40205678
- Journal Information:
- Physical Review B, Vol. 62, Issue 24; Other Information: Othernumber: PRBMDO000062000024016835000001; 076047PRB; PBD: 15 Dec 2000; ISSN 0163-1829
- Publisher:
- The American Physical Society
- Country of Publication:
- United States
- Language:
- English
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