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arXiv · 1010.4600

Gigantic enhancement of spin Seebeck effect by phonon drag

Hiroto Adachi·Ken-ichi Uchida·Eiji Saitoh·Jun-ichiro Ohe·Saburo Takahashi·Sadamichi Maekawa
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Abstract

We investigate both theoretically and experimentally a gigantic enhancement of the spin Seebeck effect in a prototypical magnet LaY$_2$Fe$_5$O$_{12}$ at low temperatures. Our theoretical analysis sheds light on the important role of phonons; the spin Seebeck effect is enormously enhanced by nonequilibrium phonons that drag the low-lying spin excitations. We further argue that this scenario gives a clue to understand the observation of the spin Seebeck effect that is unaccompanied by a global spin current, and predict that the substrate condition affects the observed signal.

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Hiroto Adachi, Ken-ichi Uchida, Eiji Saitoh, Jun-ichiro Ohe, Saburo Takahashi, Sadamichi Maekawa. 2011-01-31. Gigantic enhancement of spin Seebeck effect by phonon drag. https://doi.org/10.1063/1.3529944

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