Disordered quantum gases under control (2009)
Sanchez-Palencia, Laurent, Lewenstein, Maciej
When attempting to understand the role of disorder in condensed-matter physics, one faces severe experimental and theoretical difficulties and many questions are still open. Two of the most...
Searching for extremal PPT entangled states (2009)
Augusiak, Remigiusz, Grabowski, Janusz, Kus, Marek, Lewenstein, Maciej
We formulate a simple operational criterion allowing to judge if a given entangled state with positive partial transpose (PPTES) is extremal in the convex set of all PPTES. The criterion reduces the...
Towards measurable bounds on entanglement measures (2009)
Augusiak, Remigiusz, Lewenstein, Maciej
While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied...
Dilute gas of ultracold two-level atoms inside a cavity; generalized Dicke model (2009)
Larson, Jonas, Lewenstein, Maciej
We consider a gas of ultracold two-level atoms confined in a cavity, taking into account for atomic center-of-mass motion and cavity mode variations. By means of the generalized Dicke model, the...
Entanglement generation by collisions of quantum solitons (2009)
Lewenstein, Maciej, Malomed, Boris A.
We present general analytic expressions describing generation of the entanglement in collisions of initially uncorrelated quantum solitons. The results, obtained by means of the Born approximation,...
Disordered quantum gases under control (2009)
Sanchez-Palencia, Laurent, Lewenstein, Maciej
When attempting to understand the role of disorder in condensed-matter physics, one faces severe experimental and theoretical difficulties and many questions are still open. Two of the most...
Disordered quantum gases under control (2009)
Sanchez-Palencia, Laurent, Lewenstein, Maciej
When attempting to understand the role of disorder in condensed-matter physics, one faces severe experimental and theoretical difficulties and many questions are still open. Two of the most...
Disorder-Induced Phase Control in Superfluid Fermi-Bose Mixtures (2008)
Niederberger, Armand, Wehr, Jan, Lewenstein, Maciej, Sacha, Krzysztof
We consider a mixture of a superfluid Fermi gas of ultracold atoms and a Bose-Einstein condensate of molecules possessing a continuous U(1) (relative phase) symmetry. We study the effects that a...
Enhancement of Entanglement Percolation in Quantum Networks via Lattice Transformations (2008)
Lapeyre Jr, G. John, Wehr, Jan, Lewenstein, Maciej
We study strategies for establishing long-distance entanglement in quantum networks. Specifically, we consider networks consisting of regular lattices of nodes, in which the nearest neighbors share a...
Cold Fermi atomic gases in a pumped optical resonator (2008)
Larson, Jonas, Morigi, Giovanna, Lewenstein, Maciej
We study systems of fully polarized ultracold atomic gases obeying Fermi statistics. The atomic transition interacts dispersively with a mode of a standing-wave cavity, which is coherently pumped by...
Fermion- and Spin-Counting in Strongly Correlated Systems (2008)
Braungardt, Sibylle, De, Aditi Sen, Sen, Ujjwal, Glauber, Roy J., Lewenstein, Maciej
We apply the atom counting theory to strongly correlated Fermi systems and spin models, which can be realized with ultracold atoms. The counting distributions are typically sub-Poissonian and remain...
Entanglement Enhances Security in Secret Sharing (2008)
Demkowicz-Dobrzanski, Rafal, De, Aditi Sen, Sen, Ujjwal, Lewenstein, Maciej
We analyze tolerable quantum bit error rates in secret sharing protocols, and show that using entangled encoding states is advantageous in the case when the eavesdropping attacks are local. We also...
De, Aditi Sen, Sen, Ujjwal, Wehr, Jan, Lewenstein, Maciej
We consider a classical spin model, of two-dimensional spins, with continuous symmetry, and investigate the effect of a symmetry breaking unidirectional quenched disorder on the magnetization of the...
Collective Laser Cooling of Trapped Atoms (2007)
J. Ignacio Cirac, Maciej Lewenstein, Peter Zoller
We show that by a suciently slow repumping process, one can avoid the problems of reabsorptions in laser cooling of trapped atoms, even in the case of optically thick samples. 03.75Fi,...
Ultra-cold dipolar gases (2007)
Menotti, Chiara, Lewenstein, Maciej
We present a concise review of the physics of ultra-cold dipolar gases, based mainly on the theoretical developments in our own group. First, we discuss shortly weakly interacting ultra-cold trapped...
Quantum stability of self-organized atomic insulator-like states in optical resonators (2007)
Larson, Jonas, Fernandez-Vidal, Sonia, Morigi, Giovanna, Lewenstein, Maciej
We investigate a paradigm example of cavity quantum electrodynamics with many body systems: an ultracold atomic gas inside a pumped optical resonator. In particular, we study the stability of atomic...
Quantum Non-Demolition Detection of Strongly Correlated Systems (2007)
Eckert, Kai, Romero-Isart, Oriol, Rodriguez, Mirta, Lewenstein, Maciej, Polzik, Eugene S., Sanpera, Anna
Preparation, manipulation, and detection of strongly correlated states of quantum many body systems are among the most important goals and challenges of modern physics. Ultracold atoms offer an...
Disorder-Induced Order in Two-Component Bose-Einstein Condensates (2007)
Niederberger, Armand, Schulte, Thomas, Wehr, Jan, Lewenstein, Maciej, Sanchez-Palencia, Laurent, Sacha, Krzysztof
We propose and analyze a general mechanism of disorder-induced order in two-component Bose-Einstein condensates, analogous to corresponding effects established for XY spin models. We show that a...
Frustration, Area Law, and Interference in Quantum Spin Models (2007)
De, Aditi Sen, Sen, Ujjwal, Dziarmaga, Jacek, Sanpera, Anna, Lewenstein, Maciej
We study frustrated quantum systems from a quantum information perspective. Within this approach, we find that highly frustrated systems do not follow any general ''area law'' of block entanglement,...
Strongly Correlated States of Ultracold Rotating Dipolar Fermi Gases (2007)
Osterloh, Klaus, Barberán, Nuria, Lewenstein, Maciej
We study strongly correlated ground and excited states of rotating quasi-2D Fermi gases constituted of a small number of dipole-dipole interacting particles with dipole moments polarized...
Ultracold Bose Gases in 1D Disorder: From Lifshits Glass to Bose-Einstein Condensate (2007)
Lugan, Pierre, Clément, David, Bouyer, Philippe, Aspect, Alain, Lewenstein, Maciej, Sanchez-Palencia, Laurent
We study an ultracold Bose gas in the presence of 1D disorder for repulsive inter-atomic interactions varying from zero to the Thomas-Fermi regime. We show that for weak interactions the Bose gas...
Ultracold Bose Gases in 1D Disorder: From Lifshits Glass to Bose-Einstein Condensate (2007)
Lugan, Pierre, Clément, David, Bouyer, Philippe, Aspect, Alain, Lewenstein, Maciej, Sanchez-Palencia, Laurent
We study an ultracold Bose gas in the presence of 1D disorder for repulsive inter-atomic interactions varying from zero to the Thomas-Fermi regime. We show that for weak interactions the Bose gas...
Ultracold Bose Gases in 1D Disorder: From Lifshits Glass to Bose-Einstein Condensate (2006)
Lugan, Pierre, Clément, David, Bouyer, Philippe, Aspect, Alain, Lewenstein, Maciej, Sanchez-Palencia, Laurent
We study an ultracold Bose gas in the presence of 1D disorder for repulsive inter-atomic interactions varying from zero to the Thomas-Fermi regime. We show that for weak interactions the Bose gas...
Mott insulator states of ultracold atoms in optical resonators (2006)
Larson, Jonas, Damski, Bogdan, Morigi, Giovanna, Lewenstein, Maciej
We study the low temperature physics of an ultracold atomic gas in the potential formed inside a pumped optical resonator. Here, the height of the cavity potential, and hence the quantum state of the...
Error-Resistant Distributed Quantum Computation in Trapped Ion Chain (2006)
Braungardt, Sibylle, De, Aditi Sen, Sen, Ujjwal, Lewenstein, Maciej
We consider experimentally feasible chains of trapped ions with pseudo-spin 1/2, and find models that can potentially be used to implement error-resistant quantum computation. Similar in spirit to...
Ultracold atomic gases in optical lattices: mimicking condensed matter physics and beyond (2006)
Lewenstein, Maciej, Sanpera, Anna, Ahufinger, Veronica, Damski, Bogdan, De, Aditi Sen, Sen, Ujjwal
We review recent developments in the physics of ultracold atomic and molecular gases in optical lattices. Such systems are nearly perfect realisations of various kinds of Hubbard models, and as such...
Wehr, Jan, Niederberger, Armand, Sanchez-Palencia, Laurent, Lewenstein, Maciej
We propose a general mechanism of random-field-induced order (RFIO), in which long-range order is induced by a random field that breaks the continuous symmetry of the model. We particularly focus on...
Entaglement: from fundamentals to applications (2006)
Quantum Information, Computation and Complexity * Programme at the Institut Henri Poincaré, January 4th April 7th, 2006 * Organizers: Ph.Grangier, M.Santha and D.L.Shepelyansky * Lectures have...
Wehr, Jan, Niederberger, Armand, Sanchez-Palencia, Laurent, Lewenstein, Maciej
We propose a general mechanism of random-field-induced order (RFIO), in which long-range order is induced by a random field that breaks the continuous symmetry of the model. We particularly focus on...
Wehr, Jan, Niederberger, Armand, Sanchez-Palencia, Laurent, Lewenstein, Maciej
We propose a general mechanism of random-field-induced order (RFIO), in which long-range order is induced by a random field that breaks the continuous symmetry of the model. We particularly focus on...
Entaglement: from fundamentals to applications (2006)
Quantum Information, Computation and Complexity * Programme at the Institut Henri Poincaré, January 4th April 7th, 2006 * Organizers: Ph.Grangier, M.Santha and D.L.Shepelyansky * Lectures have...
Dynamics of F=1 87Rb condensates at finite temperatures (2005)
Mur-Petit, Jordi, Guilleumas, Montserrat, Polls, Artur, Sanpera, Anna, Lewenstein, Maciej, Bongs, Kai, ...
We investigate the dynamics of a F=1 spinor Bose-Einstein condensate of 87Rb atoms confined in a quasi-one-dimensional trap both at zero and at finite temperature. At zero temperature, we observe...
Dense coding with multipartite quantum states (2005)
Bruss, Dagmar, D'Ariano, Giacomo Mauro, Lewenstein, Maciej, Macchiavello, Chiara, De, Aditi Sen, Sen, Ujjwal
We consider generalisations of the dense coding protocol with an arbitrary number of senders and either one or two receivers, sharing a multiparty quantum state, and using a noiseless channel. For...
Laser cooling all the way down to molecular condensate (2005)
Dziarmaga, Jacek, Lewenstein, Maciej
Numerical simulations show that laser cooling of fermions on the repulsive side of the Feshbach resonance can sympathetically cool molecules well below their condensation temperature.
Laser cooling all the way down to Fermi superfluid (2004)
Dziarmaga, Jacek, Lewenstein, Maciej
Numerical simulations for realistic experimental parameters demonstrate that laser cooling on the attractive side of the Feshbach resonance can drive fermions much below the superfluid transition....
Sanpera, Anna, Kantian, Adrian, Sanchez-Palencia, Laurent, Zakrzewski, Jakub, Lewenstein, Maciej
We investigate atomic Fermi-Bose mixtures in inhomogeneous and random optical lattices in the limit of strong atom-atom interactions. We derive the effective Hamiltonian describing the dynamics of...
Sanpera, Anna, Kantian, Adrian, Sanchez-Palencia, Laurent, Zakrzewski, Jakub, Lewenstein, Maciej
We investigate atomic Fermi-Bose mixtures in inhomogeneous and random optical lattices in the limit of strong atom-atom interactions. We derive the effective Hamiltonian describing the dynamics of...
Sanpera, Anna, Kantian, Adrian, Sanchez-Palencia, Laurent, Zakrzewski, Jakub, Lewenstein, Maciej
We investigate atomic Fermi-Bose mixtures in inhomogeneous and random optical lattices in the limit of strong atom-atom interactions. We derive the effective Hamiltonian describing the dynamics of...
Entanglement properties of Gaussian states (2003)
Kraus, Barbara, Giedke, Géza, Lewenstein, Maciej, Cirac, J. Ignacio
Near-Resonant Imaging of Trapped Cold Atomic Samples (1996)
this paper is to examine the problem of imaging BEC within a cold atomic sample by coherent scattering of a weak, near-resonant, continuous-wave laser field. Two separate studies are required for the...