REGULAR
ARTICLES
SQUID Measurements of the Susceptibilities of Impurity-Helium
Condensates....................................6
J. Järvinen, C.
Paulsen, E.P.
Bernard, V.V. Khmelenko and D.M. Lee
<khmel@ccmrr.cornell.edu>
Spin Dynamics of a Trapped Spin-1 Bose Gas above the Bose-Einstein
Transition Temperature........21
Yuki Endo and Tetsuro Nikuni
< j1206620@ed.kagu.tus.ac.jp >
New Method for Measuring the Rotation Inertia of a Single 4He
Crystal..............................................47
V.L. Tsymbalenko
< VLT@isssph.kiae.ru
>
Helicon-Phonon Resonance in
PbSe....................................................................................................56
L.T. Tsymbal, Ya. B. Bazaliy, A.N. Cherkasov and V.A. Mishin
< lt_tsymbal@yahoo.com
>
Role of Coexistence of Superconductivity and Paramagnetism in
Magnetostriction of
High-TcSuperconductors....................................................................................................................63
F.
Inanir
<inanir@ktu.edu.tr >
Polaron State Screening by plasmons in a spherical
Nanocrystal.........................................................71
L.C. Fai, A. Fomethe, V.B.
Mborong, A.J.
Fotue, S. Domngang, N. Issofa and
M. Tchoffo.
<
corneliusfai@yahoo.fr>
The
2008 Fritz London Memorial Prize Winners
|
|
|
Yuriy
M. Bunkov
|
Vladimir V. Dmitriev
|
Igor A. Fomin
|
Yuriy
M. Bunkov, Vladimir V. Dmitriev, and Igor A. Fomin have
been named winners of the 2008 Fritz London Memorial Prize for
their discovery and understanding of the "Phase
Coherent Spin Precession and Spin Superfluidity of "3He-B"
This is an award for a unique
phenomenon involving spontaneous phase
coherent macroscopic precession of the magnetization
in superfluid 3He-B and the flow of spin
supercurrent [1,
2]. The latter is a magnetic counterpart of mass-current superfludity
in helium liquids and Bose-Einstein condensates (BECs) and of
charge-current superfluidity in superconductors. It is also an
example of the BEC of spin-wave excitations or magnons.
Since their discovery they have
established many other consequences
of this BEC state, such as the spin supercurrent, spin-current
Josephson effect, spin-current vortices, and nontopological solitons
(called Q-balls in high energy physics). They also developed new
measuring techniques based on coherent spin precession, which made it
possible to observe other novel effects in 3He
superfluids, such as a vortex terminating on a soliton sheet, the
observation of the Goldstone mode of the vortex with non-axisymmetric
core in 3He-B, the identification of the order
parameter
of 3He in aerogel via a measurement of the 3He-B
Leggett angle, and the observation of coherent precession in 3He-A,
to name a few.
Since its discovery by Osheroff,
Richardson and Lee in 1972,
superfluid 3He has been a fertile field of research. The
purity of the material and the
multi-dimensional order parameter manifold have made this quantum
state of triplet Cooper pairing an attractive laboratory for the
study of the superfluidity in a magnetically ordered quantum liquid
crystal environment. The system also has many properties in common
with relativistic quantum fields and has turned into a playground for
testing several new ideas relevant to particle physics and cosmology.
The unusual spin dynamics and NMR properties of superfluid 3He-B
are at the source of the discovery. Inhomogeneity in the spin
precession frequency creates spin supercurrents, which redistribute
the magnetization in such a way that the precession becomes uniform.
Traces of long-lived magnetic precessing states had been seen earlier
by Corruccini and Osheroff and also by groups at Cornell and in
Helsinki.
However
the first long-lived induction signal with a large amplitude
corresponding to the coherent precession of the whole magnetization
was discovered and understood by Borovik-Romanov, Bunkov, Dmitriev
and Mukharskii in 1984 [1]. The crucial point was the observed time
dependence of the precession frequency, which triggered the Fomin
theory of the domain with homogeneous precession, whose boundary
moves with time [2]. This domain was called the Homogeneously
Precessing Domain (HPD). The main property of such precessing states
is a coherence of the phase in the Larmor precession throughout the
whole domain, which persists even in the presence of inhomogeneous
external magnetic fields. This is the first example in nature of a
magnetic analog of the off-diagonal long-range order observed in
phase-coherent Bose condensates, superfluids, and superconductors.
Thus this phenomenon is the first true realization of spin
superfluidity.
The three winners
are all widely known low temperature physicists:
Yuriy M. Bunkov — worked at
the Kapitza
Institute in Moscow
until 1995, in the laboratory of academician A.V.S. Borovik-Romanov,
where he constructed the first nuclear demagnetization refrigerator
in Soviet Union and performed much of the early research. Since 1995
he has been “Directeur des Recherches” in the Center of Ultra Low
Temperature Research in Grenoble (now Institut NEEL), where he has
continued to
make important
contributions to the subject matter described here. He also
participates in measurements in Helsinki, Lancaster, Tokyo, Kosice and
Kyoto
where he found new types of coherent states in bulk 3He
and in 3He in aerogel, and where he has applied
his
measuring techniques based on coherent precession to quantized
vortices in rotating flow. He is well known for his work on the
Kibble-Zurek mechanism in superfluid 3He-B, the
equivalent
of cosmic string formation in cosmological phase transitions.
Vladimir V. Dmitriev —
started his career at the Kapitza Institute in Moscow in the
experimental group headed by A. Borovik-Romanov and Yu. Bunkov. He
participated in the experimental studies of superfluid 3He which led to
the original discovery of the Homogeneously Precessing Domain state as
well as in further investigations of spin superfluidity. He is
now the head of the
Ultra Low Temperature group in the Kapitza Institute and a
corresponding member of the Russian Academy of Sciences. He
significantly expanded the field of research on magnetically excited
coherent spin states with his well-known later work on the first
observations of precessing magnetic domains in Fermi liquids and in
3He in aerogel.
Igor A. Fomin — worked at
the Landau
Institute for
Theoretical Physics in Moscow and since 1993 at the Kapitza Institute
in Moscow. He is a corresponding
member of the Russian Academy of Sciences. He constructed the theory
of magnetically excited coherent quantum states and of spin
supercurrent transport and applied these to the explanation of the
actual measurements. He also suggested a theory on the order
parameter states of 3He in aerogel.
[1] A.S. Borovik-Romanov, Yu.M.
Bunkov, V.V. Dmitriev, and Yu.M.
Mukharskiy, "Long Lived Induction Decay Signal Investigations
in 3He", JETP Lett. 40, 1033
(1984).
[2] I.A. Fomin, "Long-lived induction signal and spatially
nonuniform spin precession in 3He-B",
JETP Lett. 40, 1037 (1984).
The
Fritz London
Memorial Prize
The Fritz
London Prize was created to recognize scientists who made outstanding
contributions to the advances of the field of Low Temperature
Physics. It is traditionally awarded in the first session of the
International Low Temperature Conference, which is sponsored by the
IUPAP (International Union of Pure and Applied Physics) and was first
awarded in 1957. The London Prize was first funded by grants from
the A.D. Little Company that made the Collins helium liquefiers. The
funding on a regular basis dates back to 1972 when John Bardeen gave
his portion of the Nobel Prize to Duke University for an endowment,
called "the Fritz London Fund". This was to provide support
for the annual Fritz London lecture and for the London Prize, to be
awarded at each international LT meeting. In 1994, a second endowment
was created at Duke University from a) the balance of funds remaining
from the LT20 Conference in Oregon, remitted by Russell Donnelly, and
b) a gift from Horst Meyer. This second endowment is called "Fritz
London Prize endowment" and is solely intended for the London
Prize. Further gifts to this endowment were made in 2000 and 2006 by
the Organizers of the LT22 and LT24 Conferences in Helsinki
(Finland) and in Orlando (Florida, USA). Furthermore Oxford
Instruments Inc. in Abingdon, UK, made generous gifts in cash for all
the London prizes awarded since 1996.
The
list of previous
London Prize winners reads:
1957:
N. Kurti (UK)
1960:
L.D. Landau
(USSR)
1962:
J. Bardeen (USA)
1964:
D. Schoenberg
(UK)
1966:
C.G. Gorter
(Holland)
1968:
W.M. Fairbank
(USA)
1970:
B.D. Josephson
(UK)
1972:
A.A. Abrikosov
(USSR)
1975:
J. Wheatley (USA)
1978:
G. Ahlers, W.
McMillan, J.M. Rowell (all USA)
1981:
J.D. Reppy, A.J.
Leggett, I. Rudnick (all USA)
1984:
W. Buckel
(Germany), O.V. Lounasmaa (Finland), D.J. Thouless (USA)
1987:
K.A. Mueller and
J.G. Bednorz (Switzerland), J. Kondo (Japan), J. Clarke (USA)
1990:
R.C. Dynes (USA),
P.C. Hohenberg (USA), A.I. Larkin (USSR)
1993:
A. Schmid
(Germany), D. Greywall (USA), H. Meyer (USA)
1996:
M.H.W. Chan, C.
Wieman, E.A Cornell (all USA)
1999:
D.F. Brewer (UK),
M. Krusius (Finland), W. Ketterle (USA)
2002:
R.J. Donnelly
(USA), A. Goldman (USA), W. N. Hardy (Canada)
2005:
S. Balibar
(France), J.C. Séamus Davis (USA), R. Packard (USA)
Submitted by Allen
Goldman, Chair
2008 Fritz London
Prize Committee,
and
based on the
nomination by
Academician
Alexander F. Andreev