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Atomistic switch of giant magnetoresistance and spin thermopower in graphene-like nanoribbons.

ABSTRACT: We demonstrate that the giant magnetoresistance can be switched off (on) in even- (odd-) width zigzag graphene-like nanoribbons by an atomistic gate potential or edge disorder inside the domain wall in the antiparallel (ap) magnetic configuration. A strong magneto-thermopower effect is also predicted that the spin thermopower can be greatly enhanced in the ap configuration while the charge thermopower remains low. The results extracted from the tight-binding model agree well with those obtained by first-principles simulations for edge doped graphene nanoribbons. Analytical expressions in the simplest case are obtained to facilitate qualitative analyses in general contexts.

SUBMITTER: Zhai MX

PROVIDER: S-EPMC5114670 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Atomistic switch of giant magnetoresistance and spin thermopower in graphene-like nanoribbons.

Zhai Ming-Xing MX Wang Xue-Feng XF

Scientific reports 20161118

We demonstrate that the giant magnetoresistance can be switched off (on) in even- (odd-) width zigzag graphene-like nanoribbons by an atomistic gate potential or edge disorder inside the domain wall in the antiparallel (ap) magnetic configuration. A strong magneto-thermopower effect is also predicted that the spin thermopower can be greatly enhanced in the ap configuration while the charge thermopower remains low. The results extracted from the tight-binding model agree well with those obtained ...[more]

PMID: 27857156

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