Dataset Information

Robustness of Voltage-induced Magnetocapacitance.

ABSTRACT: One of the most important achievements in the field of spintronics is the development of magnetic tunnel junctions (MTJs). MTJs exhibit a large tunneling magnetoresistance (TMR). However, TMR is strongly dependent on biasing voltage, generally, decreasing with applying bias. The rapid decay of TMR was a major deficiency of MTJs. Here we report a new phenomenon at room temperature, in which the tunneling magnetocapacitance (TMC) increases with biasing voltage in an MTJ system based on Co40Fe40B20/MgO/Co40Fe40B20. We have observed a maximum TMC value of 102% under appropriate biasing, which is the largest voltage-induced TMC effect ever reported for MTJs. We have found excellent agreement between theory and experiment for the bipolar biasing regions using Debye-Fröhlich model combined with quartic barrier approximation and spin-dependent drift-diffusion model. Based on our calculation, we predict that the voltage-induced TMC ratio could reach 1100% in MTJs with a corresponding TMR value of 604%. Our work has provided a new understanding on the voltage-induced AC spin-dependent transport in MTJs. The results reported here may open a novel pathway for spintronics applications, e.g., non-volatile memories and spin logic circuits.

SUBMITTER: Kaiju H

PROVIDER: S-EPMC6168469 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Robustness of Voltage-induced Magnetocapacitance.

Kaiju Hideo H Misawa Takahiro T Nagahama Taro T Komine Takashi T Kitakami Osamu O Fujioka Masaya M Nishii Junji J Xiao Gang G

Scientific reports 20181002 1

One of the most important achievements in the field of spintronics is the development of magnetic tunnel junctions (MTJs). MTJs exhibit a large tunneling magnetoresistance (TMR). However, TMR is strongly dependent on biasing voltage, generally, decreasing with applying bias. The rapid decay of TMR was a major deficiency of MTJs. Here we report a new phenomenon at room temperature, in which the tunneling magnetocapacitance (TMC) increases with biasing voltage in an MTJ system based on Co<sub>40</ ...[more]

PMID: 30279552

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Dataset Information

Robustness of Voltage-induced Magnetocapacitance.

Publications

Robustness of Voltage-induced Magnetocapacitance.

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