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arXiv · 1003.6099

Magneto-transport Effects in Topological Insulator Bi$_2$Se$_3$ Nanoribbons

Hao Tang·Dong Liang·Richard L. J. Qiu·Xuan P. A. Gao
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Abstract

Magneto-resistance (MR) of Bi$_2$Se$_3$ nanoribbons is studied over a broad range of temperature ($T$=300K-2K) and under various magnetic field ($B$) orientations. The MR is strongly anisotropic with the perpendicular MR much larger than the longitudinal and transverse MRs. The perpendicular MR exhibits quadratic $B$-dependence in low fields and becomes linear at high $B$. However, when $T$ increases, the perpendicular MR becomes linear over the whole magnetic field range (0-9T) up to room temperature. This unusual linear MR is discussed in the context of the linear quantum MR of the topological surface-states. We also observe the boundary-scattering effect in MR at low temperatures, which indicates that the out-of-plane Fermi momentum is much smaller the in-plane Fermi momentum, excluding the simple three-dimensional Fermi surface picture.

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Hao Tang, Dong Liang, Richard L. J. Qiu, Xuan P. A. Gao. 2010-03-31. Magneto-transport Effects in Topological Insulator Bi$_2$Se$_3$ Nanoribbons. https://arxiv.org/abs/1003.6099

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