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arXiv · 1510.05316

Two-Fluid Theory for Spin Superfluidity in Magnetic Insulators

B. Flebus·S. A. Bender·Y. Tserkovnyak·R. A. Duine
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Abstract

We investigate coupled spin and heat transport in easy-plane magnetic insulators. These materials display a continuous phase transition between normal and condensate states that is controlled by an external magnetic field. Using hydrodynamic equations supplemented by Gross-Pitaevski phenomenology and magnetoelectric circuit theory, we derive a two-fluid model to describe the dynamics of thermal and condensed magnons, and the appropriate boundary conditions in a hybrid normal-metal|magnetic-insulator|normal-metal heterostructure. We discuss how the emergent spin superfluidity can be experimentally probed via a spin Seebeck effect measurement.

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B. Flebus, S. A. Bender, Y. Tserkovnyak, R. A. Duine. 2015-10-30. Two-Fluid Theory for Spin Superfluidity in Magnetic Insulators. https://doi.org/10.1103/physrevlett.116.117201

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