Magnetoresistance in Two-Component Systems
Magnetoresistance in Two-Component Systems
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DOI：
10.1103/physrevlett.114.156601
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发表时间：
2015-04-14
影响因子：
8.6
通讯作者：
Titov, M.
中科院分区：
文献类型：
--
作者：
Alekseev, P. S.;Dmitriev, A. P.;Titov, M.
电子和空穴浓度相等的双组分系统在经典强磁场中表现出非饱和线性磁阻。由于复合，预计在电荷中性的有限尺寸样品中会出现这种效应。该现象源于由于补偿霍尔效应而在样品边缘附近产生过量的准粒子密度。边界区域的大小是电子-空穴复合长度的量级，与磁场成反比。在狭窄的样品和足够强的磁场中，边界区域占主导地位，导致线性磁阻。我们的结果与二维和三维半金属和窄带半导体（包括大多数拓扑绝缘体）相关。
Two-component systems with equal concentrations of electrons and holes exhibit nonsaturating, linear magnetoresistance in classically strong magnetic fields. The effect is predicted to occur in finite-size samples at charge neutrality due to recombination. The phenomenon originates in the excess quasiparticle density developing near the edges of the sample due to the compensated Hall effect. The size of the boundary region is of the order of the electron-hole recombination length that is inversely proportional to the magnetic field. In narrow samples and at strong enough magnetic fields, the boundary region dominates over the bulk leading to linear magnetoresistance. Our results are relevant for two-and three-dimensional semimetals and narrow band semiconductors including most of the topological insulators.