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Internal transitions of quasi-2D charged magneto-excitons in the presence of purposely introduced weak lateral potential energy variations

C. J. Meining·V. R. Whiteside·B. D. McCombe·A. B. Dzyubenko·J. G. Tischler·A. S. Bracker·D. Gammon
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Abstract

Optically detected resonance spectroscopy has been used to investigate effects of weak random lateral potential energy fluctuations on internal transitions of charged magneto-excitons (trions) in quasi two-dimensional GaAs/AlGaAs quantum-well (QW) structures. Resonant changes in the ensemble photoluminescence induced by far-infrared radiation were studied as a function of magnetic field for samples having: 1) no growth interrupts (short range well-width fluctuations), and 2) intentional growth interrupts (long range monolayer well-width differences). Only bound-to-continuum internal transitions of the negatively charged trion are observed for samples of type 1. In contrast, a feature on the high field (low energy) side of electron cyclotron resonance is seen for samples of type 2 with well widths of 14.1 and 8.4 nm. This feature is attributed to a bound-to-bound transition of the spin-triplet with non-zero oscillator strength resulting from breaking of translational symmetry.

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C. J. Meining, V. R. Whiteside, B. D. McCombe, A. B. Dzyubenko, J. G. Tischler, A. S. Bracker, D. Gammon. 2006-12-12. Internal transitions of quasi-2D charged magneto-excitons in the presence of purposely introduced weak lateral potential energy variations. https://doi.org/10.1103/physrevb.75.165301

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