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arXiv · 1606.08945

Magnetic Dirac Fermions and Chern Insulator Supported on Pristine Silicon Surface

Huixia Fu·Zheng Liu·Chao Lian·Jin Zhang·Hui Li·Jia-Tao Sun·Sheng Meng
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Abstract

Emergence of ferromagnetism in non-magnetic semiconductors is strongly desirable, especially in topological materials thanks to the possibility to achieve quantum anomalous Hall effect. Based on first-principles calculations, we propose that for Si thin film grown on metal substrate, the pristine Si(111)-root3xroot3 surface with a spontaneous weak reconstruction has a strong tendency of ferromagnetism and nontrivial topological properties, characterized by spin polarized Dirac-fermion surface states. In contrast to conventional routes relying on introduction of alien charge carriers or specially patterned substrates, the spontaneous magnetic order and spin-orbit coupling on the pristine silicon surface together gives rise to quantized anomalous Hall effect with a finite Chern number C=-1. This work suggests exciting opportunities in silicon-based spintronics and quantum computing free from alien dopants or proximity effects.

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Huixia Fu, Zheng Liu, Chao Lian, Jin Zhang, Hui Li, Jia-Tao Sun, Sheng Meng. 2016-06-29. Magnetic Dirac Fermions and Chern Insulator Supported on Pristine Silicon Surface. https://doi.org/10.1103/physrevb.94.035427

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