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Quantum corrections crossover and ferromagnetism in magnetic topological insulators.

ABSTRACT: Revelation of emerging exotic states of topological insulators (TIs) for future quantum computing applications relies on breaking time-reversal symmetry and opening a surface energy gap. Here, we report on the transport response of Bi2Te3 TI thin films in the presence of varying Cr dopants. By tracking the magnetoconductance (MC) in a low doping regime we observed a progressive crossover from weak antilocalization (WAL) to weak localization (WL) as the Cr concentration increases. In a high doping regime, however, increasing Cr concentration yields a monotonically enhanced anomalous Hall effect (AHE) accompanied by an increasing carrier density. Our results demonstrate a possibility of manipulating bulk ferromagnetism and quantum transport in magnetic TI, thus providing an alternative way for experimentally realizing exotic quantum states required by spintronic applications.

SUBMITTER: Bao L

PROVIDER: S-EPMC3739003 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Quantum corrections crossover and ferromagnetism in magnetic topological insulators.

Bao Lihong L Wang Weiyi W Meyer Nicholas N Liu Yanwen Y Zhang Cheng C Wang Kai K Ai Ping P Xiu Faxian F

Scientific reports 20130101

Revelation of emerging exotic states of topological insulators (TIs) for future quantum computing applications relies on breaking time-reversal symmetry and opening a surface energy gap. Here, we report on the transport response of Bi2Te3 TI thin films in the presence of varying Cr dopants. By tracking the magnetoconductance (MC) in a low doping regime we observed a progressive crossover from weak antilocalization (WAL) to weak localization (WL) as the Cr concentration increases. In a high dopin ...[more]

PMID: 23928713

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