|
||
|
|
||
|
Who am I?
How to
contact me
Research
interests
Selected
publications
Quantum chaos and quantum
transport with cold atoms
Classical dynamics of
laser-cooled atoms
Quantum coherence and quantum interference
Quantum optics, manipulation of the
quantum noise of
light beams
Metrology of fundamental constants
Miscellaneous
Recent invited conferences and seminars
I was born in Barbacena (see Google
Earth), a small brazilian town some
I graduated in 1982 from Pontificia Universidade Catolica (the
choice was not made on religious grounds) do Rio de Janeiro (PUC/RJ).
I got my M. Sc. also from PUC/RJ ,
working with Luiz Davidovich
on intense laser
field atomic ionization.
I moved to France in 1985 to prepare my Ph. D. degree in Laboratoire Kastler Brossel (then Laboratoire de Spectroscopie Hertzienne) de l'ENS, in Paris. I worked there with François Biraben and Lucile Julien on high-precision two-photon spectroscopy of the hydrogen atom. The subject of my Ph. D. thesis was a determination of the Rydberg constant, then the most precise measurement of that constant in the world.
I made a post-doc at CNET (the research center of France Télécom, now France Télécom R&D) with Ariel Levenson and Izo Abram, working on the manipulation of the quantum noise of light. We conceived and experimentally demonstrated a quantum device able to copy the features of a light beam without adding quantum noise to it, the Quantum cloning amplifier.
I joined the CNRS
in 1992, and I work since then in the Laboratoire de Physique des
Lasers,
Atomes et Molécules (PhLAM),
at Villeneuve d'Ascq (near Lille, the main city of the
northeast France,
From 1998 on, the Quantum Chaos group
, formed
by Pascal
Szriftgiser, Véronique
Zehnlé and myself,
with several Ph. D. students and post-docs, works in experimental and
theoretical studies of the quantum dynamics
of cold atoms in light potentials.
Call me at the office:
|
|
} |
20 33 |
{ |
64 49
|
(Office)
|
Send me a FAX:
|
|
} |
|
Send me a mail:
Bat. P5 - UFR de Physique
Université des Sciences et
Technologies de
Lille
F-59655 Villeneuve d'Ascq Cedex
France
In my professional and
passional
activity as a physicist, I have had the opportunity to work in
many
fields, doing both theoretical and experimental research:
Current
research fields
-
Experimental
studies of quantum
chaos with cold atoms
- Experimental and theoretical studies
of quantum transport of cold atoms in light potentials
- Theoretical studies of the relations
between quantum coherence and
quantum
interference
Past
research fields
-
Experimental and theoretical quantum optics (manipulation of the
quantum noise
of light, squeezing)
-
Ultra-precise
spectroscopy of the hydrogen atom, measurement of the Rydberg constant (Ph. D. thesis)
Programming
&
interfacing
-
Development
of Visual
C++ applications
(graphic applications, database
applications, etc.)
-
Development
of experiment-interfacing C++ object libraries (GPIB, data acquisition
&
processing)
I have published some 40 peer-reviewed articles in international journals, which have been cited about 500 times in the scientific literature. Below, I present a selection of the papers most representative of my scientific activity.
Click here for more complete information on my current research activity.
Click here for a more complete list of recent publications.
Research achievements
*
Kicked rotor versus
Anderson model
This work has
been chosen as an "Editors suggestion" 
by
PRL and is the
object of an "APS Viewpoint:
Spotlighting exceptional research" 
When a quantum-chaotic kicked rotor
presenting dynamical
localization (DL) is perturbed by a quasiperiodic perturbation,
dynamical
localization is destroyed. But what is the scenario followed by this
destruction? If one thinks that the well-known analogy between
dynamical
localization and the Anderson localization shall be universal, one
shall expect
that DL is preserved, but the localization length goes to infinity with
the
amplitude of the perturbation. Performing the experiment, we have
followed that this is not the case. We observe a progressive transition
from
localization to a diffusive behavior that becomes stronger as the
perturbation
increases. This shows that the above Anderson analogy is not universal
and may
depend on the precise way DL is distroyed (see Phys.
Rev. Lett. 97, 264101 (2006)). However, more recently, we have used
a
different system, in which the quasiperiodic modulation is applied as a
modulation of the intensity of the kicks. In the case in which the
system displays
three independent frequencies (corresponding, formally, to a 3D
Anderson
model), we have been able to put into evidence a quantum phase
transition which
is the kicked-rotor temporal equivalent of the condensed matter physics
Anderson metal-insulator transition (see Phys.
Rev. Lett. 101, 255702 (2008).
* Reversibility
and irreversibility in a quantum-chaotic system
The quantum-chaotic kicked rotor presents
astonishing
quantum-interference effects, as that called dynamical localization.
It
is possible to mixt-up phases deterministically in order to
suppress
such quantum interference effects (see Phys.
Rev.
Lett. 85, 2741 (2000)). However, being deterministic,
such mixing is in principle reversible:
we have demonstrated it experimentally. On the other hand, decoherence
is a
random mixing of quantum phases, and, as such, is irreversible. We have
also
demonstrated that by adding spontaneous emission in a controlled way to
our
system, the revesibility is destroyed (see Phys.
Rev. Lett. 95, 234101 (2005)).
*
Quasi-classical chaos
in the dynamics of a Bose-Einstein condensate in optical lattices
Quantum
mechanical evolution is usually linear, because Schrödinger
equation also is.
This means that in cannot display sensitivity to initial conditions and
a
chaotic behavior in the classical sense. That is why quantum chaos
(which
ususally means the behavior of a quantum system whose classical limit
is
chaotic) is very different of classical chaos. However, Bose-Einstein
condensates are more complicated objects, because they display
many-body
quantum-coherent interactions that can produce to
nonlinearities, e.g.
in the limit of the mean-field approach of Gross-Pitaevskii equation.
They are
thus able in a certain sense to display sensitivity to initial
conditions and a
kind of quasi-classical chaos. We have recently studied this situation,
and shown
that the quasi-classical behavior is compatible with the
Komolgorov-Arnol'd-Moser theorem (see Phys.
Rev.
Lett. 91, 210405 (2003)).
*
"Sub-Fourier" resonances in a quantum chaotic system
Quantum-chaotic
systems, in certain conditions, can distinguish two frequencies in a
time
smaller that the inverse of the frequency difference. This behavior,
that we
loosely call "sub-Fourier" has been identified and demonstrated for
the first time recently (see Phys. Rev.
Lett. 89,
224101 (2002)). We are now able to explain the detail mechanims
leading to
such astonishing behavior in terms of dynamics of quantum-chaotic
systems (see Europhys. Lett. 69, 327
(2005)).
Quantum
chaos and quantum transport with cold atoms
|
|
Observation of
the Anderson transition with atomic matter waves: Theory and experiment Phys. Rev. A 80, 043626 (2009), with Selected for the Virtual Journal of Atomic Quantum Fluids. |
|
|
Experimental
observation of the Anderson transition with atomic matter waves |
|
|
Tracking
quasi-classical chaos in ultracold bose gases |
|
Kicked rotor
quantum resonances in position space |
|
|
|
Quantum scaling
laws in the onset of dynamical delocalization |
|
Reversible
destruction of dynamical localization |
|
|
|
Phase-space
reconstruction of an atomic chaotic system |
|
Quantum
diffusion in the quasiperiodic kicked rotor |
|
|
|
Classical chaos
with Bose-Einstein condensates in tilted optical lattices
|
|
|
Wave-packet reconstruction
via local dynamics in a parabolic lattice |
|
|
Observation of
sub-Fourier resonances in a quantum-chaotic system |
|
|
Subrecoil Raman
spectroscopy of cold cesium atoms |
|
|
Theoretical
analysis of quantum dynamics in 1D lattices: Wannier-Stark description
|
|
|
Experimental
evidence of dynamical localization and delocalization in a
quasi-periodic driven system |
|
|
Generation of
phase-coherent laser beams for Raman spectroscopy and cooling by direct
current modulation of a diode laser |
Classical dynamics of laser-cooled atoms - cooling techniques
|
|
Doppler cooling
to the recoil limit using sharp atomic transitions with controlled
quenching |
|
|
Continuous-wave
Doppler cooling of hydrogen atoms with two-photon transitions
|
|
|
Instabilities in
a magneto-optical trap : Noise induced dynamics in an atomic system
|
|
|
Observation of
bistability in a perturbed magneto-optical trap |
Quantum coherence and quantum interference
|
|
Quantum
coherence generated by interference-induced state selectiveness
|
|
|
Raman sub-recoil
cooling using quantum interference |
|
|
Atomic velocity
class selection using quantum interference |
|
|
Quantum
coherence generated by quantum interference |
Quantum optics and laser physics
|
|
Self-similarities
in the frequency-amplitude space of a loss-modulated CO2 laser
|
|
|
Quantum optical
cloning amplifier |
|
|
Quantum
correlated twin beams |
Metrology of fundamental constants
|
|
New measurement
of the Rydberg constant by two-photon spectroscopy of hydrogen Rydberg
states |
|
|
Determination of
the Rydberg constant by Doppler-free spectroscopy of hydrogen Rydberg
states |
Invited conferences and seminars
|
July 9, 2008 |
PAMO 2008, Lille |
|
|
Apr 10, 2008 |
Department of Physics and Astronomy, University College London, UK |
|
|
Sep 1, 2005 |
Congrès
général conjoint de |
|
|
Feb 3, 2004 |
Laboratoire Kastler Brossel, ENS, Paris, France |
|
|
Sept. 5, 2003 |
COLOQ 8, Toulouse, France (French conference on lasers and quantum optics) |
|
|
May 9, 2003 |
26th ENFMC, Caxambu, Brazil (Brazilian conference on condensed matter physics) |
|
v.1.69 (17/11/2009)