Abstract
Spin superfluidity, coherent spin precession, and magnon BEC are intensively investigated theoretically and experimentally nowadays. Meanwhile, clear definition and differentiation between these related phenomena is needed. It is argued that spin stiffness, which leads to existence of coherent spin precession and dissipationless spin supercurrents, is a necessary but not sufficient condition for spin superfluidity. The latter is defined as a possibility of spin transport on macroscopical distances with sufficiently large spin supercurrents. This possibility is realized at special topology of the magnetic-order-parameter space, such as, e.g., that in easy-plane antiferromagnets. It is argued that an arbitrarily chosen formal criterion for the existence of magnon BEC has no connection with conditions for observation of macroscopic dissipationless spin transport.
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Notes
König et al. [16] came independently to a similar conclusion concerning dissipationless spin transport in thin film ferromagnets.
References
L.N. Kozlov, L.A. Maximov, Zh. Eksp. Teor. Fiz. 48, 1184 (1965) [Sov. Phys. JETP 21, 790 (1965)]
M. Vuorio, J. Phys. C 7, 5 (1974)
L.R. Corruccini, D.D. Osheroff, Phys. Rev. Lett. 34, 564 (1975)
Y.E. Lozovik, V.I. Yudson, Pis’ma Zh. Eksp. Teor. Fiz. 25, 18 (1977) [JETP Lett. 25, 14 (1977)]
S.I. Shevchenko, Fiz. Nizk. Temp. 3, 605 (1977) [Sov. J. Low Temp. Phys. 3, 293 (1977)]
E.B. Sonin, Pis’ma Zh. Eksp. Teor. Fiz. 25, 95 (1977) [JETP Lett. 25, 84 (1977)]
E.B. Sonin, Solid State Commun. 25, 253 (1978)
E.B. Sonin, Zh. Eksp. Teor. Fiz. 74, 2097 (1978) [Sov. Phys. JETP 47, 1091 (1978)]
E.B. Sonin, Usp. Fiz. Nauk 137, 267 (1982) [Sov. Phys. Usp. 25, 409 (1982)]
A.S. Borovik-Romanov, Y. Bunkov, V.V. Dmitriev, Y. Mukharskii, Pis’ma Zh. Eksp. Teor. Fiz. 40, 256 (1984) [JETP Lett. 40, 1033 (1984)]
Y. Bunkov, In W.P. Halperin Progress of Low Temperature Physics, vol. 14 (Elsevier, Amsterdam, 1995), p. 68
E.B. Sonin, Adv. Phys. 59, 181 (2010)
Y.M. Bunkov, G.E. Volovik, Spin superfluidity and magnon BEC. arXiv:1003.4889
B.I. Halperin, P.C. Hohenberg, Phys. Rev. B 188, 898 (1968)
R.R. Guseinov, L.V. Keldysh, Zh. Eksp. Teor. Fiz. 63, 2255 (1972) [Sov. Phys. JETP 36, 1193 (1972)]
J. König, M.C. Bønsager, A.H. MacDonald, Phys. Rev. Lett. 87, 187202 (2001)
A.V. Nikiforov, E.B. Sonin, Zh. Eksp. Teor. Fiz. 85, 642 (1983) [Sov. Phys. JETP 58, 373 (1983)]
A.S. Borovik-Romanov, Y. Bunkov, V.V. Dmitriev, Y. Mukharskii, D.A. Sergatskov, AIP Conf. Proc. 194, 27 (1989)
I.A. Fomin, Physica B 169, 153 (1991)
Y.M. Bunkov, E.M. Alakshin, R.R. Gazizulin, A.V. Klochkov, V.V. Kuzmin, V.S. Lvov, M.S. Tagirov, Phys. Rev. Lett. 108, 177002 (2012)
E.B. Sonin, Pis’ma Zh. Eksp. Teor. Fiz. 45, 586 (1987) [JETP Lett. 45, 747 (1987)]
I.A. Fomin, Zh. Eksp. Teor. Fiz. 94, 112 (1988) [Sov. Phys. JETP 67, 1148 (1988)]
E.B. Sonin, Pis’ma Zh. Eksp. Teor. Fiz. 88, 238 (2008) [JETP Lett. 88, 205 (2008)]
T. Giamarchi, C. Rüegg, O. Tchernyshyov, Nat. Phys. 4, 198 (2008)
S.O. Demokritov, V.E. Demidov, O. Dzyapko, G.A. Melkov, A.A. Serga, B. Hillebrands, A.N. Slavin, Nature (London) 443, 430 (2006)
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The author appreciates supports by the grant of the Israel Academy of Sciences and Humanities and by the EU-FP7 program Microkelvin.
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Sonin, E.B. Spin Superfluidity, Coherent Spin Precession, and Magnon BEC. J Low Temp Phys 171, 757–768 (2013). https://doi.org/10.1007/s10909-012-0802-5
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DOI: https://doi.org/10.1007/s10909-012-0802-5