3,002 research outputs found
The temperature dependence of quantum spin pumping generated using electron spin resonance with three-magnon splittings
On the basis of the Schwinger-Keldysh formalism, we have closely investigated
the temperature dependence of quantum spin pumping by electron spin resonance.
We have clarified that three-magnon splittings excite non-zero modes of magnons
and characterize the temperature dependence of quantum spin pumping. Our
theoretical result qualitatively agrees with the experiment by Czeschka et al.
that the mixing conductance is little influenced by temperature [F. D. Czeschka
et al., Phys. Rev. Lett., 107, 046601 (2011)].Comment: 16 pages, 5 figures, clear pictures are available at URL specified in
the documen
Temperature dependence of spin currents in one- and three-dimensional insulators
The temperature dependence of spin currents in insulators at the finite
temperature near zero Kelvin is theoretically studied. The spin currents are
carried by Jordan-Wigner fermions and magnons in one- and three- dimensional
insulators. The quasiparticle description of one-dimensional spin systems is
valid only in the finite temperature near zero Kelvin. These spin currents are
generated by the external magnetic field gradient along the quantization axis
and also by the two-particle interaction gradient. In one-dimensional
insulators, quantum fluctuations are strong and the spin current carried by
Jordan-Wigner fermions shows the stronger dependence on temperatures than the
one by magnons.Comment: 11 pages, 2 tables, accepted for publication in Int.J.Mod.Phys.
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