Spin superfluidity and magnon BEC

Abstract

The spin superfluidity -- superfluidity in the magnetic subsystem of a condensed matter - is manifested as the spontaneous phase-coherent precession of spins first discovered in 1984 in 3He-B. This superfluid current of spins - spin supercurrent - is one more representative of superfluid currents known or discussed in other systems, such as the superfluid current of mass and atoms in superfluid 4He; superfluid current of electric charge in superconductors; superfluid current of hypercharge in Standard Model of particle physics; superfluid baryonic current and current of chiral charge in quark matter; etc. Spin superfluidity can be described in terms of the Bose condensation of spin waves - magnons. We discuss different phases of magnon superfluidity, including those in magnetic trap; and signatures of magnons superfluidity: (i) spin supercurrent, which transports the magnetization on a macroscopic distance more than 1 cm long; (ii) spin current Josephson effect which shows interference between two condensates; (iii) spin current vortex - a topological defect which is an analog of a quantized vortex in superfluids, of an Abrikosov vortex in superconductors, and cosmic strings in relativistic theories; (iv) Goldstone modes related to the broken U(1) symmetry - phonons in the spin-superfluid magnon gas; etc. We also touch the topic of spin supercurrent in general including spin Hall and intrinsic quantum spin Hall effects.

62 pages, 18 figures, prepared as Chapter IV of the book "Novel Superfluids", eds. K. H. Bennemann and J. B. Ketterson

References in corpus (25)

• Topological Insulators
• Topological insulators and superconductors
• Quantised Vortices in an Exciton-Polariton Fluid
• Bose-Einstein condensation of photons in an optical microcavity
• Bose-Einstein Condensation in Magnetic Insulators
• Quantum Anomalies in Dense Matter
• Detecting the Majorana fermion surface state of ${}^3$He-B through spin relaxation
• Bose-Einstein Condensation of Magnons in Cs2CuCl4
• Non-Abelian hydrodynamics and the flow of spin in spin-orbit coupled substances
• Bose-Einstein condensation of magnons in superfluid 3He
• Magnon condensation into Q-ball in 3He-B
• Topological invariant for superfluid 3He-B and quantum phase transitions
• Strong orientational effect of stretched aerogel on the 3He order parameter
• Self-localization of magnon Bose-Einstein condensates in the ground state and on excited levels: from harmonic to box-like trapping potential
• Bose-Einstein condensation of magnons under incoherent pumping
• Generation of nonground-state Bose-Einstein condensates by modulating atomic interactions
• Hydrodynamic theory of coupled current and magnetization dynamics in spin-textured ferromagnets
• The Ginzburg-Landau model of Bose-Einstein condensation of magnons
• Anomalous Attenuation of Transverse Sound in 3He
• On the Bose-Einstein Condensation of Rotons
• Spin Hall effect in a Doped Mott Insulator
• Solution of the problem of catastrophic relaxation of homogeneous spin precession in superfluid ${}^3$He-B
• Phonons in magnon superfluid and symmetry breaking field
• On the problem of catastrophic relaxation in superfluid 3-He-B
• Spin-precession vortex and spin-precession supercurrent stability in ${}^3$He-B

Cited by in corpus (11)

• Dirty-boson physics with magnetic insulators
• Light Higgs channel of the resonant decay of magnon condensate in superfluid ${}^3$He-B
• Phase Diagram for Magnon Condensate in Yttrium Iron Garnet Film
• Axion wind detection with the homogeneous precession domain of superfluid helium-3
• Relaxation of Bose-Einstein Condensates of Magnons in Magneto-Textural Traps in Superfluid ${}^3$He-B
• On Josephson effects in insulating spin systems
• Topological matter: graphene and superfluid 3He
• Spin superfluidity, coherent spin precession, and magnon BEC
• The magnonic superfluid droplet at room temperature
• Bose-Einstein condensation of magnons in spin pumping systems
• Conventional magnon BEC in YIG film