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arXiv · 0802.2711

Quantum Anomalous Hall Effect in Hg$_{1-y}$Mn$_{y}$Te Quantum Wells

Chao-Xing Liu·Xiao-Liang Qi·Xi Dai·Zhong Fang·Shou-Cheng Zhang
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Abstract

The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict that a new phenomenon, the quantum anomalous Hall effect, can be realized in Hg$_{1-y}$Mn$_{y}$Te quantum wells, without the external magnetic field and the associated Landau levels. This effect arises purely from the spin polarization of the $Mn$ atoms, and the quantized Hall conductance is predicted for a range of quantum well thickness and the concentration of the $Mn$ atoms. This effect enables dissipationless charge current in spintronics devices.

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Chao-Xing Liu, Xiao-Liang Qi, Xi Dai, Zhong Fang, Shou-Cheng Zhang. 2008-02-19. Quantum Anomalous Hall Effect in Hg$_{1-y}$Mn$_{y}$Te Quantum Wells. https://doi.org/10.1103/physrevlett.101.146802

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