Optical Anisotropy of Non-Polar Surfaces of Fe-Doped GaN Crystal

Abstract

Abstract: In this paper, the polarization luminescence characteristics of the near-band-edge peak and Fe³⁺ related emission peaks(⁴T₁(G)-⁶A₁(S)) of the non-polar surfaces including a-plane {1120} and m-plane {1100} of Fe-doped GaN crystal were studied by low-temperature photoluminescence(PL) measurement. The results show that the optical anisotropy of a-plane and m-plane are similar. When the linearly polarized electric-field vector E is parallel to the c-direction [0001] (E//c), the intensity of GaN near-band-edge peak is the lowest, and the intensity of Fe³⁺ zero-phonon line (1.299 eV) is the strongest. The degree of polarization of Fe³⁺ zero-phonon line is greater than that of near-band-edge peak. The degree of polarization of near-band-edge peak of a-plane is 26%, while the degree of polarization of Fe³⁺ zero-phonon line reaches up to 55% and 58% of a-plane and m-plane GaN, respectively. The polarization characteristics of Fe³⁺ fine peak and the additional lines are further measured at 5 K. The results show that, except for one weak peak, other peaks are consistent with the polarization characteristics of Fe³⁺ zero-phonon line. This study is helpful to expand the application of Fe-doped GaN crystal in the field of novel optical and electrical devices.

Key words: GaN, Fe doping, semi-insulating, non-polar surface, optical anisotropy, optical and electrical property, polarized light

CLC Number:

O734
TN304

WU Yuanmeng, HU Junjie, WANG Miao, YI Juemin, ZHANG Yumin, WANG Jianfeng, XU Ke. Optical Anisotropy of Non-Polar Surfaces of Fe-Doped GaN Crystal[J]. Journal of Synthetic Crystals, 2022, 51(6): 996-1002.

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