TY - JOUR
T1 - Microscopic calculation of thermally induced spin-transfer torques
AU - Kohno, Hiroshi
AU - Hiraoka, Yuuki
AU - Hatami, Moosa
AU - Bauer, Gerrit E W
PY - 2016/9/15
Y1 - 2016/9/15
N2 - Spin-transfer torques, both reactive and dissipative, induced by temperature gradients in conducting ferromagnets are calculated microscopically for smooth magnetization textures. Temperature gradients are treated à la Luttinger by introducing a fictitious gravitational field that couples to the energy density. The thermal torque coefficients obtained by the Kubo formula contain unphysical terms that diverge towards zero temperature. Such terms are caused by equilibrium components and should be subtracted before applying the Einstein-Luttinger relation. Only by following this procedure a familiar Mott-like formula is obtained for the dissipative spin-transfer torque. The result indicates that a fictitious field that couples to the entropy rather than energy would solve the issue from the outset.
AB - Spin-transfer torques, both reactive and dissipative, induced by temperature gradients in conducting ferromagnets are calculated microscopically for smooth magnetization textures. Temperature gradients are treated à la Luttinger by introducing a fictitious gravitational field that couples to the energy density. The thermal torque coefficients obtained by the Kubo formula contain unphysical terms that diverge towards zero temperature. Such terms are caused by equilibrium components and should be subtracted before applying the Einstein-Luttinger relation. Only by following this procedure a familiar Mott-like formula is obtained for the dissipative spin-transfer torque. The result indicates that a fictitious field that couples to the entropy rather than energy would solve the issue from the outset.
UR - http://resolver.tudelft.nl/uuid:a977bbd2-6cb3-49f0-ad04-5192a93928bb
UR - http://www.scopus.com/inward/record.url?scp=84990961017&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.94.104417
DO - 10.1103/PhysRevB.94.104417
M3 - Article
AN - SCOPUS:84990961017
SN - 1098-0121
VL - 94
SP - 1
EP - 12
JO - Physical Review B (Condensed Matter and Materials Physics)
JF - Physical Review B (Condensed Matter and Materials Physics)
IS - 10
M1 - 104417
ER -