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Spin inversion in graphene spin valves by gate-tunable magnetic proximity effect at one-dimensional contacts.

ABSTRACT: Graphene has remarkable opportunities for spintronics due to its high mobility and long spin diffusion length, especially when encapsulated in hexagonal boron nitride (h-BN). Here, we demonstrate gate-tunable spin transport in such encapsulated graphene-based spin valves with one-dimensional (1D) ferromagnetic edge contacts. An electrostatic backgate tunes the Fermi level of graphene to probe different energy levels of the spin-polarized density of states (DOS) of the 1D ferromagnetic contact, which interact through a magnetic proximity effect (MPE) that induces ferromagnetism in graphene. In contrast to conventional spin valves, where switching between high- and low-resistance configuration requires magnetization reversal by an applied magnetic field or a high-density spin-polarized current, we provide an alternative path with the gate-controlled spin inversion in graphene.

SUBMITTER: Xu J

PROVIDER: S-EPMC6054683 | biostudies-other | 2018 Jul

REPOSITORIES: biostudies-other

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Spin inversion in graphene spin valves by gate-tunable magnetic proximity effect at one-dimensional contacts.

Xu Jinsong J Singh Simranjeet S Katoch Jyoti J Wu Guanzhong G Zhu Tiancong T Žutić Igor I Kawakami Roland K RK

Nature communications 20180720 1

Graphene has remarkable opportunities for spintronics due to its high mobility and long spin diffusion length, especially when encapsulated in hexagonal boron nitride (h-BN). Here, we demonstrate gate-tunable spin transport in such encapsulated graphene-based spin valves with one-dimensional (1D) ferromagnetic edge contacts. An electrostatic backgate tunes the Fermi level of graphene to probe different energy levels of the spin-polarized density of states (DOS) of the 1D ferromagnetic contact, w ...[more]

PMID: 30030444

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