Giant magnetoresistance and spin Seebeck coefficient in zigzag α-graphyne nanoribbons.

Nanoscale

College of Physics, Optoelectronics and Energy, Soochow University, 1 Shizi Street, Suzhou, Jiangsu 215006, China.

Published: October 2014

We investigate the spin-dependent electric and thermoelectric properties of ferromagnetic zigzag α-graphyne nanoribbons (ZαGNRs) using density-functional theory combined with non-equilibrium Green's function method. A giant magnetoresistance is obtained in the pristine even-width ZαGNRs and can be as high as 10(6)%. However, for the doped systems, a large magnetoresistance behavior may appear in the odd-width ZαGNRs rather than the even-width ones. This suggests that the magnetoresistance can be manipulated in a wide range by the dopants on the edges of ZαGNRs. Another interesting phenomenon is that in the B- and N-doped even-width ZαGNRs the spin Seebeck coefficient is always larger than the charge Seebeck coefficient, and a pure-spin-current thermospin device can be achieved at specific temperatures.

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http://dx.doi.org/10.1039/c4nr02426eDOI Listing

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