The optical Aharonov-Bohm effect in a quantum ring was investigated in terms of magnetic field dependence of excitons and biexcitons. The fine exciton states of quantized orbital angular momentum in a quantum ring were considered theoretically, and the presence of quantum beats was predicted as evidence of the quantum coherence of the fine exciton states. In the case of GaAs/GaAlAs quantum rings grown by the droplet epitaxy, we found various disorder effects are associated such as structure anisotropy, localization, and internal electric field, resulting in a modulation of the oscillation periods. Additionally, we found that a strongly correlated exciton pair can be formed in a single quantum ring similar to the Wigner molecule. In this case, the biexciton emission energy changes abruptly at transition magnetic fields with a fractional oscillation period compared to that of the exciton, the so-called fractional optical Aharonov-Bohm oscillations.

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Light-Controlled Optical Aharonov-Bohm Oscillations in a Single GaAs/AlGaAs Quantum Ring

  • H. Yang,
  • S. Yi,
  • H. D. Kim,
  • K. C. Je,
  • J. S. Kim,
  • J. H. Kyhm,
  • M. Eto,
  • L. S. Dang,
  • M. Potemski,
  • R. A. Taylor,
  • J. D. Song,
  • K. Kyhm

摘要

The optical Aharonov-Bohm effect in a quantum ring was investigated in terms of magnetic field dependence of excitons and biexcitons. The fine exciton states of quantized orbital angular momentum in a quantum ring were considered theoretically, and the presence of quantum beats was predicted as evidence of the quantum coherence of the fine exciton states. In the case of GaAs/GaAlAs quantum rings grown by the droplet epitaxy, we found various disorder effects are associated such as structure anisotropy, localization, and internal electric field, resulting in a modulation of the oscillation periods. Additionally, we found that a strongly correlated exciton pair can be formed in a single quantum ring similar to the Wigner molecule. In this case, the biexciton emission energy changes abruptly at transition magnetic fields with a fractional oscillation period compared to that of the exciton, the so-called fractional optical Aharonov-Bohm oscillations.