Yuri Michailowitsch Bunkow

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Juri Michailowitsch Bunkow ( Russian Юрий Михайлович Буньков , English transcription Yuri Bunkov ; born August 29, 1950 in Stavropol ) is a Russian experimental solid-state physicist who is known for the discovery of spin superfluidity .

Bunkow came from a family of geologists, attended a special school for physics and mathematics in Moscow (School No. 2) and studied at the Moscow Institute of Physics and Technology. In 1974 he received his doctorate and in 1985 he completed his habilitation (Russian doctorate, with a dissertation on NMR studies on superfluid helium-3). From 1974 to 1995 he was at the Kapiza Institute, from 1986 as a senior scientist. He was there in the group of Viktor-Andrei Stanislawowitsch Borowik-Romanow . There he discovered with Vladimir Dmitrijew and Juri Mucharski (who worked there as students) the spin superfluidity. It was expressed in NMR studies on helium-3 B as an area of ​​coherent Larmor precession (HPD, Homogeneously Precessing Domains), whereby inhomogeneities in the precession due to supercurrents in the spin (magnetization) are similar to those in superconductivity (charge) and superfluid or Bose-Einstein- Condensates (mass) were balanced. It is also a Bose-Einstein condensate (BEC) from magnons . Theoretician Igor Fomin gave a theoretical explanation in the 1980s . He had previously installed the first magnetic cooling system with adiabatic nuclear demagnetization in the Soviet Union. 1989 to 1995 he took part in experiments at the University of Lancaster. He has been researching for CNRS since 1995 at the Institut Néel in Grenoble, where he is Research Director. Before that, he was visiting professor in Grenoble from 1992. He is also a professor at Kazan University.

In the He 3 B phase (which has a complex phase structure) he also discovered experimental analogues to cosmological and quantum field theoretical phenomena, such as cosmological strings (as eddies in the spin supercurrent) and Majorana quasiparticles. Goldstone modes were detected as early as the 1980s (phonons in the HPD analogous to the second sound in superfluids). In the 2000s he discovered Q-balls , nontopological solitons that were also originally introduced in QFT.

In 2008, together with Japanese colleagues, he discovered coherent precession in the helium-3-A phase, which was embedded in externally deformed aerogels .

In 2008 he received the Fritz London Memorial Prize with Vladimir Dmitrijew and Igor A. Fomin . In addition to the theoretician Fomin, he also worked with the theoretician Grigori Jefimowitsch Wolowik (Volovik). He has been a full member of the Academia Europaea since 2010 .

Fonts

  • with AS Borovik-Romanov, VV Dmitriev, Yu.M. Mukharskiy: Long Lived Induction Decay Signal Investigations in 3 He , JETP Lett., Volume 40, 1984, p. 1033.
  • with VV Dmitriev, Yu.M. Mukharskiy: Twist oscillations of homogeneous pre-cession domain in 3 He-B , JETP Lett., Volume 43, 1986, pp. 168–171 (Goldstone Mode)
  • with AS Borovik-Romanov: Spin supercurrent and magnetic relaxation in He-3 , Harwood Academic Publ. 1990.
  • with VVDmitriev, Yu.M. Mukharskiy, Low frequency oscillations of the homogeneously prececessing domain in 3 He-B , Physica B, Volume 178, 1992, pp. 196-201 (Goldstone Mode).
  • Persistent signal; coherent NMR state trapped by orbital texture , J. Low Temp. Phys., Volume 138, 2005, pp. 753-758, (Q-Ball)
  • with GE Volovik: Magnon condensation into a Q-ball in 3He-B , Phys. Rev. Lett., Volume 98, 2007, p. 265302.
  • with T. Sato, T. Kunimatsu, K. Izumina, A. Matsubara, M. Kubota, T. Mizusaki: Coherent precession of magnetization in the superfluid 3He A-phase , Phys. Rev. Lett., Volume 101, 2008, p. 055301.
  • with GE Volovik: Bose-Einstein Condensation of Magnons in Superfluid 3He , J. Low Temperature Physics, Volume 150, 2008, pp 135-144.
  • with GE Volovik: Magnon BEC in superfluid 3He-A , JETP Lett., Volume 89, 2009, pp. 306-310.
  • with GE Volovik: Magnon BEC and spin superfluidity: a He3 primer , Arxiv 2009
  • Spin superfluidity and magnons Bose-Einstein-Condensation , Physics Uspekhi, August 2010, online
  • with GE Volovik: Spin superfluidity and magnon BEC , in: Int. Ser. Monogr. Phys. 156, 2013, pp. 253-311, Arxiv
  • with Rasul Gazizuzin: Observation of Majorana Quasiparticles Surface States in Superfluid 3He-B by Heat Capacity Measurements , Arxiv 2016
  • with Vladimir Safonov: Magnon Condensation and Spin Superfluidity , Arxiv 2017
  • Spin Supercurrent , J. of Magnetism and Magnetic Materials 2017, 1, Arxiv (originally from 2007)

Web links

Individual evidence

  1. ↑ Since He 3 has spin 1/2 and is a fermion, the superconductivity there corresponds to a Cooper pair formation as in the superconductor, the Cooper pairs there have spin and angular momentum 1 (p-wave)
  2. ↑ Roster Yury Bunkov. Academia Europaea, accessed August 30, 2017 .
personal data
SURNAME Bunkow, Yuri Mikhailovich
ALTERNATIVE NAMES Bunkov, Yuri; Буньков, Юрий Михайлович
BRIEF DESCRIPTION Russian physicist
DATE OF BIRTH August 29, 1950
PLACE OF BIRTH Stavropol