arXiv 0907.30172009-07-17cond-mat.quant-gas

Spin drag in noncondensed Bose gases

R. A. Duine, H. T. C. Stoof

DOI：: 10.1103/PhysRevLett.103.170401

英文摘要：

We show how time-dependent magnetic fields lead to spin motive forces and spin drag in a spinor Bose gas. We propose to observe these effects in a toroidal trap and analyze this particular proposal in some detail. In the linear-response regime we define a transport coefficient that is analogous to the usual drag resistivity in electron bilayer systems. Due to Bose enhancement of atom-atom scattering, this coefficient strongly increases as temperature is lowered. We also investigate the effects of heating.

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