Le Journal de Physique IV 03 (1993) C5-311-C5-314
The electronic structure of a shallow acceptor and its bound exciton confined in GaAs/AlGaAs quantum wellsP.O. HOLTZ1, Q.X. ZHAO1, B. MONEMAR1, C. HARRIS1, M. SUNDARAM2, J.L. MERZ2 and A.C. GOSSARD2
1 Department of Physics and Measurement Technology, Linköping University, 581 83 Linköping, Sweden
2 Center for Quantized Electronic Structures (QUEST), University of California at Santa Barbara, Santa Barbara, CA 93106, U.S.A.
The exciton bound (BE) at the shallow Be acceptor confined in a narrow GaAs/AlGaAs quantum well (QW) has been investigated by means of selective photoluminescence (SPL) and PL excitation (PLE) experiments. For the shallow acceptor, several excited states have been observed as two-hole transition (THT) satellites of the BE. The heavy hole (hh)-like excited nS(Γ6) acceptor states dominate the satellite spectrum, but also the light hole (lh)-like excited 2S(Γ7) and the parity forbidden transition to the 2P3/2 excited state have been monitored in SPL spectra. When detecting a THT satellite, the 1S(Γ6) hh-like acceptor ground state has been spectrally resolved from the 1S(Γ7) lh-like state in PLE spectra. Several BE states have been theoretically predicted and observed in PLE spectra with the J=5/2 state at lowest energy, like in bulk GaAs. The proposed interpretation of the acceptor hh- and lh-states is confirmed by SPL and PLE experiments in the presence of an applied magnetic field and in polarized PLE measurements. An effective g-value for the acceptor BE recombination in varying degree of confinement is derived from these Zeeman measurements.
© EDP Sciences 1993