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arXiv · 1608.07034

Tuning of few-electron states and optical absorption anisotropy in GaAs quantum rings

Zhenhua Wu·Jian Li·J. Li·H. Yin·Yu Liu
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Abstract

The electronic and optical properties of a GaAs quantum ring (QR) with few electrons in the presence of the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI) have been investigated theoretically. Configuration interaction (CI) method is employed to calculate the eigenvalues and eigenstates of the multiple-electron QR accurately. Our numerical results demonstrate that the symmetry breaking induced by the RSOI and DSOI leads to an anisotropic distribution of multi-electron states. The Coulomb interaction offers additional modulation of the electron distribution and thus the optical absorption indices in the quantum rings. By tuning the magnetic/electric fields and/or electron numbers in a quantum ring, one can change its optical property significantly. Our theory provides a new way to control multi-electron states and optical properties of QR by hybrid modulations or by electrical means only.

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Zhenhua Wu, Jian Li, J. Li, H. Yin, Yu Liu. 2016-08-25. Tuning of few-electron states and optical absorption anisotropy in GaAs quantum rings. https://doi.org/10.1039/c7cp05675c

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