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arXiv · 1001.1578

Monopole Current and Unconventional Hall Response on Topological Insulator

Jiadong Zang·Naoto Nagaosa
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Abstract

We study theoretically the charged current above a topological insulator (TI) separated by a ferromagnetic insulating layer. An unconventional Hall response occurs in the conducting layer on top of the TI which approaches to a constant value independent of R for R< >l, where R is the separation between TI and conducting layer and l is the screening length. In the comoving frame, it can be interpreted as a monopole current attached to the TI surface. The same mechanism gives the Hall response and deflection of the electron beam injected to the surface of insulating ferromagnet. A realistic estimate of an order of magnitude shows that both effects give reasonably large signal experimentally accessible.

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Jiadong Zang, Naoto Nagaosa. 2010-01-11. Monopole Current and Unconventional Hall Response on Topological Insulator. https://doi.org/10.1103/physrevb.81.245125

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