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Huge magnetoresistance in topological insulator spin-valves at room temperature.

ABSTRACT: Topological insulators (TI) have extremely high potential in spintronic applications. Here, a topological insulators thin-film (TITF) spin valve with the use of the segment gate-controlled potential exhibits a huge magnetoresistance (MR) value higher than 1000% at room temperature which is more than 50 times the MR of typical topological insulators (TI) spin-valves. A high spin-polarized current is provided by the band structure generated by the tunable segment potential. The results reveal a very large resistance difference between the parallel and antiparallel configurations. The MR effect is strongly influenced by the thin-film thickness, the gate potential, the gate size, and the distribution. The proposed results will help to not only improve the room-temperature performance of the spin-valves but also enhance the applications of magnetic memories and spintronic devices.

SUBMITTER: Tseng P

PROVIDER: S-EPMC8175690 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Huge magnetoresistance in topological insulator spin-valves at room temperature.

Tseng Peng P Chen Jyun-Wei JW Hsueh Wen-Jeng WJ

Scientific reports 20210603 1

Topological insulators (TI) have extremely high potential in spintronic applications. Here, a topological insulators thin-film (TITF) spin valve with the use of the segment gate-controlled potential exhibits a huge magnetoresistance (MR) value higher than 1000% at room temperature which is more than 50 times the MR of typical topological insulators (TI) spin-valves. A high spin-polarized current is provided by the band structure generated by the tunable segment potential. The results reveal a ve ...[more]

PMID: 34083654

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