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arXiv · 0706.3965

Unambiguous symmetry assignment for the top valence band of ZnO by magneto-optical studies of the free A-exciton state

Lu Ding·Chunlei Yang·Hongtao He·Fengyi Jiang·Jiannong Wang·Zikang Tang·Bradley A. Foreman·Weikun Ge
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Abstract

We studied the circular polarization and angular dependences of the magneto-photoluminescence spectra of the free A-exciton 1S state in wurtzite ZnO at T = 5 K. The circular polarization properties of the spectra clearly indicate that the top valence band has Gamma_7 symmetry. The out-of-plane component of the magnetic field, which is parallel to the sample's c axis, leads to linear Zeeman splitting of both the dipole-allowed Gamma_5 exciton state and the weakly allowed Gamma_1/Gamma_2 exciton states. The in-plane field, which is perpendicular to the c axis, increases the oscillator strength of the weak Gamma_1/Gamma_2 states by forming a mixed exciton state.

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Lu Ding, Chunlei Yang, Hongtao He, Fengyi Jiang, Jiannong Wang, Zikang Tang, Bradley A. Foreman, Weikun Ge. 2007-06-27. Unambiguous symmetry assignment for the top valence band of ZnO by magneto-optical studies of the free A-exciton state. https://arxiv.org/abs/0706.3965

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