Photoluminescence quenching by optical bias in AlGaAs/GaAs single quantum wells

Anomalous photoluminescence characteristics are reported for AlGaAs/GaAs single quantum wells with one-monolayer-thick InAs inserted at the center of the GaAs well under an external electric field. The photoluminescence produced by exciting only the quantum well is strongly quenched when simultaneous excitation is performed using a high-energy light which can excite both the quantum well and the AlGaAs barrier layers. Since no prominent increase in the photocurrent accompanies the photoluminescence quenching, an efficient recombination center becomes operative under the simultaneous high-energy excitation. A carrier trapping center in AlGaAs which becomes active as a nonradiative recombination center after trapping carriers is considered to explain the observed result.