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arXiv · 1408.6909

Giant magnetoresistance and spin Seebeck coefficient in zigzag a-graphyne nanoribbons

M. X. Zhai·X. F. Wang·P. Vasilopoulos·Y. S. Liu·Y. J. Dong·L. Zhou·Y. J. Jiang·W. L. You
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Abstract

We investigate the spin-dependent electric and thermoelectric properties of ferromagnetic zigzag-graphyne nanoribbons (ZGNRs) using the density-functional theory combined with the non-equilibrium Green's function method. A giant magnetoresistance is obtained in the pristine even-width ZGNRs and can be as high as 10e6 %. However, for the doped systems, a large magnetoresistance behavior may appear in the odd-width ZGNRs rather than the even-width ones. This suggests that the magnetoresistance can be manipulated in a wide range by the dopants on edges of ZGNRs. Another interesting phenomenon is that in the B- and N-doped even-width ZGNRs 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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M. X. Zhai, X. F. Wang, P. Vasilopoulos, Y. S. Liu, Y. J. Dong, L. Zhou, Y. J. Jiang, W. L. You. 2014-08-29. Giant magnetoresistance and spin Seebeck coefficient in zigzag a-graphyne nanoribbons. https://doi.org/10.1039/c4nr02426e

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