Pierre-Etienne Wolf
Institut Néel
25 Avenue des Martyrs
BP 166
38042 Grenoble Cedex
E-mail: pierre-etienne.myname "at" grenoble.cnrs.fr
Bureau: M 109
Téléphone: +33 (0)4 76 88 12 73
Fax: +33 (0)4 76 87 50 60
Member of the HELFA team of the Institut Néel
Link to the
HELFA pages on
Institut Néel website
Research activities
As a low-temperature physicist, the core of my past and present activities
concerns the physics of Helium. Over the years, I have studied the
roughening transition of solid Helium 4, the properties of highly
spin-polarized liquid Helium 3, atomization processes in liquid helium, and
phase transitions of Helium 4 confined in porous media. The common feature
of these studies is that they use Helium as a model system for different
general physical problems, in fields ranging from statistical and quantum
physics to hydrodynamics and soft matter.
Although most of these topics concern fundamental physics, some of them are
directly related to cryogenic applications (atomization in cryogenic rocket
engines, cooling of the Large Hadron Collider). Our cryogenic expertise
led my colleague Laurent Puech and myself to be involved in a project of
solar thermal propulsion for satellites (storage of liquid hydrogen during
long spatial missions).
I also appreciate forgetting about leaks problems by working at room
temperature. When I arrived in Grenoble, I thus studied during several
years light propagation in disordered media. In a funny way, some of the
concepts of that time are now useful for our present light scattering
studies at low temperature. More recently, I learned about biophysics
during a sabbatical stay at Princeton University. And I bridged low
temperature helium physics and medecine in a collaboration aimed at
producing hyperpolarized 3He for lung imaging.
Recent research and teaching administration
2002-2006 : Université Joseph Fourier : responsable
du master 2 R Physique pour l'Instrumentation
2007 : President of the organizing committee of
the French Physical Society (SFP) general meeting
Learn about this meeting on its website
2006-2008 : Coordinator of the project HEVEPOR of
the National Agency for Research (ANR)
This project involves
groups in Montpellier (GES), Grenoble (Institut Nél-MCBT), and Paris (LPTMC). Its
goal is to elucidate open questions concerning the condensation and
evaporation of fluids in porous media using porous glasses such as silica
aerogels as porous media and helium as a fluid.
Some selected references and their context
On the roughening transition (with S. Balibar
and colleagues in Groupe de Physique des Solides de l'ENS, Paris)
- "Crystal growth and crystal curvature near roughening transitions
in hcp 4He"
Wolf-PE; Gallet-F; Balibar-S; Rolley-E
Journal-de-Physique. Nov. 1985; 46(11)
- "Measurements of the Kapitza resistance and Onsager
cross-coefficient for the 4He crystal-superfluid interface"
Wolf-PE; Edwards-DO; Balibar-S
Journal of Low-Temperature Physics. June 1983; 51(5-6): 489-504
Light propagation in random media (with G.
Maret (HFML), R. Maynard and E. Akkermans (CRTBT) in Grenoble)
Light propagation in random media is generally described by a transport
theory, which assumes that the interferences between different paths
average to zero. This is analogous to the transport theory for electrons
in metals. In fact, as in metals, the interference between time-reversed
paths survives to the
averaging process. In electronic systems, this gives rise to a decrease of
the conductivity (weak localisation), which increases with the ratio of
the wavelength to the mean free
path. The same phenomenon exists for light, and is responsible for the
so-called coherent backscattering effect, which is an enhancement of the
light retroreflected from the medium. This effect was first demonstrated in
1985 by Kuga and Ishimaru, van Albada and Lagendijk, and Maret and myself,
and initially studied, among others, by ourselves in collaboration with R. Maynard
and E. Akkermans. This field then continued to develop (universal
fluctuations, strong disorder), in particular in Georg Maret's
successive groups. See his
"website" for latest news ! For some of our first papers, see
- "Optical coherent backscattering by random media: an experimental
study"
Wolf-PE; Maret-G; Akkermans-E; Maynard-R
Journal-de-Physique. Jan. 1988; 49(1): 63-75
- "Multiple light scattering from disordered media. The effect of
Brownian motion of scatterers"
MARET-G; WOLF-P-E
Zeitschrift-fur-Physik-B-Condensed-matter. 1987; 65 (4) : 409-413
This last paper extends the quasi elastic light scattering (QELS) to the
case of strong multiple scattering, and is at the origin of the technique
now known as DWS, or diffusing wave spectroscopy, described in the
following book chapter:
- "Dynamic correlation with multiply scattered light"
D.J. PINE, D.A. WEITZ, P.M. CHAIKIN, E. HERBOLZHEIMER, G. MARET, P.E.
WOLF
in "Scattering and Localization of Classical Waves in Random
Media",
edited by Ping Sheng, World Scientific Series on Condensed Matter
Physics (1990).
Thermodynamics and transport in spin-polarized liquid
3He (with L. Puech in Grenoble)
Liquid 3He is a prototype of a strongly correlated fermionic system.
Our measurements exploit the fast melting of highly polarized solid
3He, a technique introduced by Castaing and Nozieres in 1979, to reach
very large polarizations in this system, corresponding to effective
magnetic fields in excess of 200 T. Successive improvements of the
method have enabled us to cool the polarized liquid down to 50 mK, well
into the degenerate regime. Measurements of the transport and
thermodynamic properties in this regime probe the effect of the Pauli
principle in presence of strong correlations.
An overview of our work (context, theoretical background, experimental techniques, results and meaning of these
results) is given in the last issue
of Progress in Low
Temperature Physics (Volume 15)
You can download
here
its table of contents and introduction.
In these experiments, the 3He nuclear polarization is measured by high
field (11 T) SQUID magnetometry. The set-up built to achieve this
difficult task is described in
-
"
High field SQUID magnetometer for studying spin-polarized 3He
"
M. BRAVIN, S.A.J. WIEGERS, P.E. WOLF, L. PUECH
J. Low Temp. Phys.88 (1992), 723.
In parallel to the rapid melting technique, we also made experiments in
large static fields, in collaboration with S.A.J. Wiegers, from Nijmegen
University.
These experiments use a sensitive high-field torque magnetometer
described in
-
"
A sensitive and versatile torque magnetometer for use in high magnetic fields.
"
S.A.J. WIEGERS, A.S. van STEENBERGEN, M.E. JEUKEN, M. BRAVIN, P.E. WOLF, G. REMENYI, J.A.A.J. PERENBOOM and J.C. MAAN.
Review of Scientific Instruments, 69, 2369 (1998)
4He in porous media
(with L. Puech in Grenoble)
Diphasic flow of 4He
(collaboration with P. Thibault and L. Puech, and B. Rousset and colleagues in CEA-Grenoble)
Others
Two papers connected to a sabbatical in Stan Leibler's lab at
Princeton. The first one uses optical means to inactivate motor
proteins, the second extends the FRAP (fluorescence recovery after
photobleaching) technique to the case of confined 1D diffusion, with an
analysis very similar to that of the spin relaxation in the
experimental cell used for measuring the viscosity of spin polarized
3He!
- " Chromophore-Assisted Light Inactivation and Self
Organization of Microtubules and Motors"
T. SURREY, M. E. ELOWITZ, P.E. WOLF, F. YANG, F. NEDELEC, K. SHOKAT
and S. LEIBLER.
Proc. Natl. Acad. Sci. USA 95, 4293 (1998)
- " Protein Mobility in the Cytoplasm of E.Coli "
M. E. ELOWITZ, M. G. SURETTE, P.E. WOLF, J. B. STOCK and S.
LEIBLER.
Journal of Bacteriology 181 , 197 (1999)
With G. Vermeulen, we have collaborated with an INSERM team in Grenoble
to produce polarized 3He for lung imaging by brute force polarization at
low temperature (1-4 K). Although the obtained polarization is modest
with respect to what is currently feasible with optical pumping, it was
nearly 3 orders of magnitude larger than the equilibrium polarization
in the MRI magnet, allowing to optimize different imaging sequences for
the transiently hyperpolarized gas.
- " Low Temperature Polarized 3He for MRI Applications"
F. KOBER, P.E. WOLF, J.L. LEVIEL, G. VERMEULEN, A. DELON,
J. DEROUARD, M. DECORPS, A. ZIEGLER
Magnetic Resonance in Medicine 41, 1084 (1999)
- " Rat lung MRI using low-temperature prepolarized Helium-3
"
F. KOBER, P.E. WOLF, J.L. LEVIEL, G. VERMEULEN, G. DUHAMEL, L. LAMALLE,
M. DECORPS et A. ZIEGLER
Magn. Reson. Med 45, 1130 (2001)
Full publication list (updated Nov, 2007)
pdf version
