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arXiv · 1808.08930

Topological quantum phase transition in magnetic topological insulator upon magnetization rotation

Minoru Kawamura·Masataka Mogi·Ryutaro Yoshimi·Atsushi Tsukazaki·Yusuke Kozuka·Kei. S. Takahashi·Masashi Kawasaki·Yoshinori Tokura
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Abstract

We report a continuous phase transition between quantum-anomalous-Hall and trivial-insulator phases in a magnetic topological insulator upon magnetization rotation. The Hall conductivity transits from one plateau of quantized Hall conductivity $e^2/h$ to the other plateau of zero Hall conductivity. The transition curves taken at various temperatures cross almost at a single point, exemplifying the critical behavior of the transition. The slope of the transition curves follows a power-law temperature dependence with a critical exponent of $-0.61$. This suggests a common underlying origin in the plateau transitions between the QAH and quantum Hall systems, which is a percolation of one-dimensional chiral edge channels.

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Minoru Kawamura, Masataka Mogi, Ryutaro Yoshimi, Atsushi Tsukazaki, Yusuke Kozuka, Kei. S. Takahashi, Masashi Kawasaki, Yoshinori Tokura. 2018-08-27. Topological quantum phase transition in magnetic topological insulator upon magnetization rotation. https://doi.org/10.1103/physrevb.98.140404

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