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arXiv · 1211.3220

Observation of momentum space semi-localization in Si-doped $β$-Ga$_2$O$_3$

P. Richard·T. Sato·S. Souma·N. Nakayama·H. W. Liu·K. Iwaya·T. Hitosugi·H. Aida·H. Ding·T. Takahashi
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Abstract

We performed an angle-resolved photoemission spectroscopy study of Si-doped $β$-Ga$_2$O$_3$. We observed very small photoemission intensity near the Fermi level corresponding to non-dispersive states assigned to Si impurities. We show evidence for a quantization of these states that is accompanied by a confinement in the momentum space consistent with a real-space finite confinement observed in a previous scanning tunneling microscopy study. Our results suggest that this semi-localization in the conjugate spaces plays a crucial role in the electronic conduction of this material.

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P. Richard, T. Sato, S. Souma, N. Nakayama, H. W. Liu, K. Iwaya, T. Hitosugi, H. Aida, H. Ding, T. Takahashi. 2012-12-06. Observation of momentum space semi-localization in Si-doped $β$-Ga$_2$O$_3$. https://doi.org/10.1063/1.4769109

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