TY - JOUR
T1 - Dynamically induced heat rectification in quantum systems
JF - Phys. Rev. E
Y1 - 2019
A1 - Riera-Campeny, Andreu
A1 - Mehboudi, Mohammad
A1 - Pons, Marisa
A1 - Sanpera, Anna
VL - 99
UR - https://link.aps.org/doi/10.1103/PhysRevE.99.032126
ER -
TY - JOUR
T1 - Thermometry in the quantum regime: recent theoretical progress
JF - Journal of Physics A: Mathematical and Theoretical
Y1 - 2019
A1 - Mehboudi, Mohammad
A1 - Sanpera, Anna
A1 - Correa, Luis A
VL - 52
UR - https://iopscience.iop.org/article/10.1088/1751-8121/ab2828/meta
JO - J. Phys. A: Math. Theor.
ER -
TY - JOUR
T1 - Fluctuation-dissipation theorem for non-equilibrium quantum systems
JF - Quantum
Y1 - 2018
A1 - Mehboudi, Mohammad
A1 - Sanpera, Anna
A1 - Parrondo, Juan M. R.
VL - 2
UR - https://quantum-journal.orghttps://quantum-journal.org/papers/q-2018-05-24-66/
JO - Quantum
ER -
TY - JOUR
T1 - Genuine quantum correlations in quantum many-body systems: a review of recent progress
JF - Reports on Progress in Physics
Y1 - 2018
A1 - De Chiara, Gabriele
A1 - Sanpera, Anna
VL - 81
JO - Rep. Prog. Phys.
ER -
TY - JOUR
T1 - Separability of diagonal symmetric states: a quadratic conic optimization problem
JF - Quantum
Y1 - 2018
A1 - Tura, Jordi
A1 - Aloy, Albert
A1 - Quesada, Ruben
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
VL - 2
UR - https://quantum-journal.orghttps://quantum-journal.org/papers/q-2018-01-12-45/
JO - Quantum
ER -
TY - JOUR
T1 - Enhancement of low-temperature thermometry by strong coupling
JF - PHYSICAL REVIEW A
Y1 - 2017
A1 - Correa, Luis A.
A1 - Perarnau-Llobet, Marti
A1 - Hovhannisyan, Karen V.
A1 - Hernandez-Santana, Senaida
A1 - Mehboudi, Mohammad
A1 - Sanpera, Anna
AB - We consider the problem of estimating the temperature T of a very cold equilibrium sample. The temperature estimates are drawn from measurements performed on a quantum Brownian probe strongly coupled to it. We model this scenario by resorting to the canonical Caldeira-Leggett Hamiltonian and find analytically the exact stationary state of the probe for arbitrary coupling strength. In general, the probe does not reach thermal equilibrium with the sample, due to their nonperturbative interaction. We argue that this is advantageous for low-temperature thermometry, as we show in our model that (i) the thermometric precision at low T can be significantly enhanced by strengthening the probe-sampling coupling, (ii) the variance of a suitable quadrature of our Brownian thermometer can yield temperature estimates with nearly minimal statistical uncertainty, and (iii) the spectral density of the probe-sample coupling may be engineered to further improve thermometric performance. These observations may find applications in practical nanoscale thermometry at low temperatures-a regime which is particularly relevant to quantum technologies.
VL - 96
ER -
TY - JOUR
T1 - Entanglement and nonlocality in diagonal symmetric states of
JF - Physical Review A
Y1 - 2017
A1 - Quesada, Ruben
A1 - Rana, Swapan
A1 - Sanpera, Anna
VL - 95
UR - http://link.aps.org/doi/10.1103/PhysRevA.95.042128http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.95.042128/fulltexthttp://link.aps.org/article/10.1103/PhysRevA.95.042128
JO - Phys. Rev. A
ER -
TY - JOUR
T1 - Magnetic phases of spin-1 lattice gases with random interactions
JF - PHYSICAL REVIEW B
Y1 - 2017
A1 - McAlpine, Kenneth D.
A1 - Paganelli, Simone
A1 - Ciuchi, Sergio
A1 - Sanpera, Anna
A1 - De Chiara, Gabriele
AB - A spin-1 atomic gas in an optical lattice, in the unit-filling Mott insulator (MI) phase and in the presence of disordered spin-dependent interaction, is considered. In this regime, at zero temperature, the system is well described by a disordered rotationally invariant spin-1 bilinear-biquadratic model. We study, via the density matrix renormalization group algorithm, a bounded disorder model such that the spin interactions can be locally either ferromagnetic or antiferromagnetic. Random interactions induce the appearance of a disordered ferromagnetic phase characterized by a nonvanishing value of the spin glass order parameter across the boundary between a ferromagnetic phase and a dimer phase exhibiting random singlet order. We also study the distribution of the block entanglement entropy in the different regions.
VL - 95
ER -
TY - JOUR
T1 - Quantum optics and frontiers of physics: the third quantum revolution
JF - Physica Scripta
Y1 - 2017
A1 - Celi, Alessio
A1 - Sanpera, Anna
A1 - Ahufinger, Veronica
A1 - Lewenstein, Maciej
VL - 92
UR - http://stacks.iop.org/1402-4896/92/i=1/a=013003?key=crossref.1d2d860672d166faed2db4e6d4b217abhttp://stacks.iop.org/1402-4896/92/i=1/a=013003/pdfhttp://stacks.iop.org/1402-4896/92/i=1/a=013003?key=crossref.1d2d860672d166faed2db4e6d4b217ab
JO - Phys. Scr.
ER -
TY - JOUR
T1 - Vortex stability in Bose-Einstein condensates in the presence of disorder
JF - Physical Review A
Y1 - 2017
A1 - Pons, Marisa
A1 - Sanpera, Anna
VL - 95
UR - https://link.aps.org/doi/10.1103/PhysRevA.95.033626http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.95.033626/fulltexthttp://link.aps.org/article/10.1103/PhysRevA.95.033626
JO - Phys. Rev. A
ER -
TY - JOUR
T1 - Achieving sub-shot-noise sensing at finite temperatures
JF - Physical Review A
Y1 - 2016
A1 - Mehboudi, Mohammad
A1 - Correa, Luis A.
A1 - Sanpera, Anna
VL - 94
IS - 4
JO - Phys. Rev. A
ER -
TY - JOUR
T1 - Individual Quantum Probes for Optimal Thermometry
JF - Physical Review Letters
Y1 - 2015
A1 - Correa, Luis A.
A1 - Mehboudi, Mohammad
A1 - Adesso, Gerardo
A1 - Sanpera, Anna
VL - 114
IS - 22
JO - Phys. Rev. Lett.
ER -
TY - JOUR
T1 - Best separable approximation of multipartite diagonal symmetric states
JF - Physical Review A
Y1 - 2014
A1 - Quesada, Ruben
A1 - Sanpera, Anna
AB - The structural study of entanglement in multipartite systems is hindered by the lack of necessary and sufficient operational criteria able to discriminate among the various entanglement properties of a given mixed state. Here, we pursue a different route to the study of multipartite entanglement based on the closeness of a multipartite state to the set of separable ones. In particular, we analyze multipartite diagonal symmetric N-qubit states and provide the analytical expression for their best separable approximation (BSA, [Phys. Rev. Lett. 80, 2261 (1998)]), that is, their unique convex decomposition into a separable part and an entangled part, with maximal weight of the separable part.
VL - 89
IS - 5
JO - Phys. Rev. A
ER -
TY - JOUR
T1 - Bound entanglement in the Jaynes–Cummings model
JF - Journal of Physics B: Atomic, Molecular and Optical Physics
Y1 - 2013
A1 - Quesada, Nicolás
A1 - Sanpera, Anna
VL - 46
IS - 22
JO - J. Phys. B: At. Mol. Opt. Phys.
ER -
TY - JOUR
T1 - Beyond pure state entanglement for atomic ensembles
JF - New Journal of Physics
Y1 - 2012
A1 - Julia Stasińska
A1 - Paganelli, Simone
A1 - Sanpera, Anna
AB - We analyze multipartite entanglement between atomic ensembles within quantum matter–light interfaces. In our proposal, a polarized light beam crosses sequentially several polarized atomic ensembles impinging on each of them at a given angle $\alpha$ i . These angles are crucial parameters for shaping the entanglement since they are directly connected to the appropriate combinations of the collective atomic spins that are squeezed. We exploit such a scheme to go beyond the pure state paradigm proposing realistic experimental settings to address multipartite mixed state entanglement in continuous variables.
VL - 14
UR - http://stacks.iop.org/1367-2630/14/i=3/a=033034
ER -
TY - JOUR
T1 - Glass to superfluid transition in dirty bosons on a lattice
JF - New J. Phys.
Y1 - 2012
A1 - Julia Stasińska
A1 - Massignan, Pietro
A1 - Bishop, Michael
A1 - Wehr, Jan
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
AB - We investigate the interplay between disorder and interactions in a Bose gas on a lattice in presence of randomly localized impurities. We compare the performance of two theoretical methods, the simple version of multi-orbital Hartree-Fock and the common Gross-Pitaevskii approach, showing how the former gives a very good approximation to the ground state in the limit of weak interactions, where the superfluid fraction is small. We further prove rigorously that for this class of disorder the fractal dimension of the ground state d* tends to the physical dimension in the thermodynamic limit. This allows us to introduce a quantity, the fractional occupation, which gives insightful information on the crossover from a Lifshits to a Bose glass. Finally, we compare temperature and interaction effects, highlighting similarities and intrinsic differences.
VL - 14
UR - http://arxiv.org/abs/1111.3494
ER -
TY - JOUR
T1 - Disordered spinor Bose-Hubbard model
JF - Phys. Rev. A
Y1 - 2011
A1 - Ł{\k a}cki, M.
A1 - Paganelli, Simone
A1 - Ahufinger, V.
A1 - Sanpera, Anna
A1 - Zakrzewski, J.
KW - Condensed Matter - Other Condensed Matter
KW - Quantum Physics
AB - We study the zero-temperature phase diagram of the disordered spin-1 Bose-Hubbard model in a two-dimensional square lattice. To this aim, we use a mean-field Gutzwiller ansatz and a probabilistic mean-field perturbation theory. The spin interaction induces two different regimes, corresponding to a ferromagnetic and antiferromagnetic order. In the ferromagnetic case, the introduction of disorder reproduces analogous features of the disordered scalar Bose-Hubbard model, consisting in the formation of a Bose glass phase between Mott insulator lobes. In the antiferromagnetic regime, the phase diagram differs more from the scalar case. Disorder in the chemical potential can lead to the disappearance of Mott insulator lobes with an odd-integer filling factor and, for sufficiently strong spin coupling, to Bose glass of singlets between even-filling Mott insulator lobes. Disorder in the spinor coupling parameter results in the appearance of a Bose glass phase only between the n and the n+1 lobes for n odd. Disorder in the scalar Hubbard interaction inhibits Mott insulator regions for occupation larger than a critical value.
VL - 83
UR - http://link.aps.org/doi/10.1103/PhysRevA.83.013605
ER -
TY - JOUR
T1 - Spin Effects in Bose-Glass Phases
JF - J Low Temp Phys
Y1 - 2011
A1 - Paganelli, Simone
A1 - Ła̧cki, Mateusz
A1 - Ahufinger, Veronica
A1 - Zakrzewski, Jakub
A1 - Sanpera, Anna
VL - 165
UR - http://www.springerlink.com/content/10w5036068935773/
ER -
TY - THES
T1 - Quantum Information with continuous variable systems
T2 - Departament de Físca, Grup de Física Teòria: Informació i fenòmens quàntics
Y1 - 2010
A1 - Rodó, Carles
AB - This thesis deals with the study of quantum communication protocols with Continuous Variable (CV) systems. CV systems are those described by canonical conjugated coordinates $x$ and $p$ endowed with infinite dimensional Hilbert spaces, thus involving a complex mathematical structure. A special class of CV states, are the so-called Gaussian states. We present a protocol that permits to extract quantum keys from entangled Gaussian states. Differently from discrete systems, Gaussian entangled states cannot be distilled with Gaussian operations only. However it was already shown, that it is still possible to extract perfectly correlated classical bits to establish secret random keys. We properly modify the protocol using bipartite Gaussian entanglement to perform quantum key distribution in an efficient and realistic way. We describe and demonstrate security in front of different possible attacks on the communication, detailing the resources demanded. We also consider a simple 3-partite protocol known as Byzantine Agreement. It is an old classical communication problem in which parties (with possible traitors among them) can only communicate pairwise, while trying to reach a common decision. Classically, there is a bound in the maximal number of possible traitors that can be involved in the game. Nevertheless, a quantum solution exist. We show that solution within CV using multipartite entangled Gaussian states and Gaussian operations. Furthermore, we show under which premises concerning entanglement content of the state, noise, inefficient homodyne detectors, our protocol is efficient and applicable with present technology. It is known that in spite of their exceptional role within the space of all CV states, in fact, Gaussian states are not always the best candidates to perform quantum information tasks. Thus, we tackle the problem of quantification of correlations (quantum and/or classical) between two CV modes (Gaussian and non-Gaussian). We propose to define correlations between the two modes as the maximal number of correlated bits extracted via local quadrature measurements on each mode. On Gaussian states, where entanglement is accessible via their covariance matrix our quantification majorizes entanglement, reducing to an entanglement monotone for pure states. For non-Gaussian states, such as photonic Bell states, photon subtracted states and mixtures of Gaussian states, the bit quadrature correlations are shown to be also a monotonic function of the negativity. This quantification yields a feasible, operational way to measure non-Gaussian entanglement in current experiments by means of direct homodyne detection, without needing a complete state tomography with the same complexity as if dealing with Gaussian states. Finally we focus to atomic ensembles described as CV. Measurement induced entanglement between two macroscopical atomic samples was reported experimentally in 2001. There, the interaction between a single laser pulse propagating through two spatially separated atomic samples combined with a final projective measurement on the light led to the creation of pure EPR entanglement between the two samples. We show how to generate, manipulate and detect mesoscopic entanglement between an arbitrary number of atomic samples through a quantum non-demolition matter-light interface. Our proposal extends in a non-trivial way for multipartite entanglement (GHZ and cluster-like) without needing local magnetic fields. Moreover, we show quite surprisingly that given the irreversible character of a measurement, the interaction of the atomic sample with a second pulse light can modify and even reverse the entangling action of the first one leaving the samples in a separable state.
JF - Departament de Físca, Grup de Física Teòria: Informació i fenòmens quàntics
PB - Universitat Autònoma de Barcelona
CY - Barcelona
VL - PhD
ER -
TY - JOUR
T1 - Manipulating mesoscopic multipartite entanglement with atom-light interfaces
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2009
A1 - Julia Stasińska
A1 - Rodó, Carles
A1 - Paganelli, Simone
A1 - Sanpera, Anna
A1 - Birkl, G.
KW - atom-photon collisions
KW - EPR paradox
KW - measurement theory
KW - mesoscopic entanglement
KW - multipartite entanglement
KW - quantum entanglement
KW - quantum optics
AB - Entanglementbetween two macroscopic atomic ensembles induced by measurement on anancillary light system has proven to be a powerful methodfor engineering quantum memories and quantum state transfer. Here weinvestigate the feasibility of such methods for generation, manipulation, anddetection of genuine multipartite entanglement (Greenberger-Horne-Zeilinger and clusterlike states) betweenmesoscopic atomic ensembles without the need of individual addressing ofthe samples. Our results extend in a nontrivial way theEinstein-Podolsky-Rosen entanglement between two macroscopic gas samples reported experimentally in[B. Julsgaard, A. Kozhekin, and E. Polzik, Nature (London) 413,400 (2001)]. We find that under realistic conditions, a secondorthogonal light pulse interacting with the atomic samples, can modifyand even reverse the entangling action of the first oneleaving the samples in a separable state. ©2009 The American Physical Society
PB - APS
VL - 80
UR - http://link.aps.org/abstract/PRA/v80/e062304
ER -
TY - JOUR
T1 - Preparation of decoherence-free cluster states with optical superlattices
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2009
A1 - Jiang, Liang
A1 - Rey, Ana Maria
A1 - Romero-Isart, Oriol
A1 - Garcia-Ripoll, Juan Jose
A1 - Sanpera, Anna
A1 - Lukin, Mikhail D.
KW - atom-photon collisions
KW - ground states
KW - optical multilayers
KW - quantum optics
KW - superlattices
VL - 79
UR - http://link.aps.org/abstract/PRA/v79/e022309 http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PLRAAN000079000002022309000001&idtype=cvips&gifs=yes http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PLRAAN000079000002
ER -
TY - JOUR
T1 - Double-barrier potentials for matter-wave gap solitons
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2008
A1 - Ahufinger, Veronica
A1 - Malomed, B. A.
A1 - Birkl, G.
A1 - Corbalán, Ramon
A1 - Sanpera, Anna
KW - Bose-Einstein condensation
KW - Fabry-Perot interferometers
KW - matter waves
KW - optical solitons
VL - 78
UR - http://link.aps.org/abstract/PRA/v78/e013608 http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PLRAAN000078000001013608000001&idtype=cvips&gifs=yes
ER -
TY - JOUR
T1 - Frustration, Area Law, and Interference in Quantum Spin Models
JF - Physical Review Letters
Y1 - 2008
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Dziarmaga, Jacek
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
VL - 101
UR - http://link.aps.org/abstract/PRL/v101/e187202
ER -
TY - JOUR
T1 - Multipartite continuous-variable solution for the Byzantine agreement problem
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2008
A1 - Neigovzen, Rodion
A1 - Rodó, Carles
A1 - Adesso, Gerardo
A1 - Sanpera, Anna
KW - Gaussian processes
KW - homodyne detection
KW - quantum cryptography
KW - quantum entanglement
VL - 77
UR - http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PLRAAN000077000006062307000001&idtype=cvips&prog=normal
ER -
TY - JOUR
T1 - Operational Quantification of Continuous-Variable Correlations
JF - Physical Review Letters
Y1 - 2008
A1 - Rodó, Carles
A1 - Adesso, Gerardo
A1 - Sanpera, Anna
VL - 100
UR - http://link.aps.org/abstract/PRL/v100/e110505
ER -
TY - JOUR
T1 - Probing Quantum Magnetism with Cold Atoms
JF - Science
Y1 - 2008
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
VL - 319
UR - http://www.sciencemag.org/cgi/content/full/319/5861/292?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=probing+quantum+magnetism&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT
ER -
TY - JOUR
T1 - Quantum non-demolition detection of strongly correlated systems
JF - Nature Physics
Y1 - 2008
A1 - Eckert, Kai
A1 - Romero-Isart, Oriol
A1 - Rodriguez, Mirta
A1 - Lewenstein, Maciej
A1 - Polzik, Eugene S.
A1 - Sanpera, Anna
VL - 4
UR - http://www.nature.com/nphys/journal/v4/n1/full/nphys776.html
ER -
TY - JOUR
T1 - Efficiency in Quantum Key Distribution Protocols with Entangled Gaussian States
JF - Open Systems & Information Dynamics
Y1 - 2007
A1 - Rodó, Carles
A1 - Romero-Isart, Oriol
A1 - Eckert, Kai
A1 - Sanpera, Anna
KW - gaussian states
KW - quantum cryptography
KW - quantum key distribution
AB - Abstract Quantum key distribution (QKD) refers to specific quantum strategies which permit the secure distribution of a secret key between two parties that wish to communicate secretly. Quantum cryptography has proven unconditionally secure in ideal scenarios and has been successfully implemented using quantum states with finite (discrete) as well as infinite (continuous) degrees of freedom. Here, we analyze the efficiency of QKD protocols that use as a resource entangled gaussian states and gaussian operations only. In this framework, it has already been shown that QKD is possible [1] but the issue of its efficiency has not been considered. We propose a figure of merit (the efficiency E) to quantify the number of classical correlated bits that can be used to distill a key from a sample of N entangled states. We relate the efficiency of the protocol to the entanglement and purity of the states shared between the parties.
VL - 14
UR - http://dx.doi.org/10.1007/s11080-007-9030-x
ER -
TY - JOUR
T1 - Efficient quantum-state transfer in spin chains via adiabatic passage
JF - New Journal of Physics
Y1 - 2007
A1 - Eckert, Kai
A1 - Romero-Isart, Oriol
A1 - Sanpera, Anna
KW - spin chain
KW - state transfer
VL - 9
UR - http://iopscience.iop.org/1367-2630/9/5/155/pdf/1367-2630\_9\_5\_155.pdf
ER -
TY - JOUR
T1 - Predicting Spinor Condensate Dynamics from Simple Principles
JF - Physical Review Letters
Y1 - 2007
A1 - Moreno-Cardoner, M.
A1 - Mur-Petit, J.
A1 - Guilleumas, M.
A1 - Polls, Artur
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
KW - Bose-Einstein condensation
KW - entropy
VL - 99
UR - http://link.aps.org/abstract/PRL/v99/e020404
ER -
TY - JOUR
T1 - Quantum Polarization Spectroscopy of Ultracold Spinor Gases
JF - Physical Review Letters
Y1 - 2007
A1 - Eckert, Kai
A1 - Zawitkowski, L.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
A1 - Polzik, Eugene S.
VL - 98
UR - http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PRLTAO000098000010100404000001&idtype=cvips&prog=normal
ER -
TY - JOUR
T1 - Quantum state transfer in spin-1 chains
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2007
A1 - Romero-Isart, Oriol
A1 - Eckert, Kai
A1 - Sanpera, Anna
KW - ferromagnetic materials
KW - ground states
KW - Heisenberg model
KW - magnetic transitions
KW - quantum entanglement
KW - spin chain
KW - spin systems
KW - state transfer
VL - 75
UR - http://link.aps.org/abstract/PRA/v75/e050303
ER -
TY - JOUR
T1 - Quantum switches and quantum memories for matter-wave lattice solitons
JF - New Journal of Physics
Y1 - 2007
A1 - Ahufinger, Veronica
A1 - Mebrahtu, A.
A1 - Corbalán, Ramon
A1 - Sanpera, Anna
VL - 9
UR - http://iopscience.iop.org/1367-2630/9/1/004/pdf/1367-2630\_9\_1\_004.pdf
ER -
TY - JOUR
T1 - Transport and entanglement generation in the Bose-Hubbard model
JF - Journal of Physics A: Mathematical and General
Y1 - 2007
A1 - Romero-Isart, Oriol
A1 - Eckert, Kai
A1 - Rodó, Carles
A1 - Sanpera, Anna
VL - 40
UR - http://www.iop.org/EJ/article/1751-8121/40/28/S11/a7\_28\_s11.pdf
ER -
TY - JOUR
T1 - Trapped Ion Chain as a Neural Network: Error Resistant Quantum Computation
JF - Physical Review Letters
Y1 - 2007
A1 - Pons, Marisa
A1 - Ahufinger, Veronica
A1 - Wunderlich, Christof
A1 - Sanpera, Anna
A1 - Braungardt, Sibylle
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Lewenstein, Maciej
KW - neural networks
KW - quantum computation
VL - 98
UR - http://link.aps.org/abstract/PRL/v98/e023003
ER -
TY - JOUR
T1 - Ultracold atomic Bose and Fermi spinor gases in optical lattices
JF - New Journal of Physics
Y1 - 2007
A1 - Eckert, Kai
A1 - Zawitkowski, L.
A1 - Leskinen, M. J.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
KW - optical lattices
VL - 9
UR - http://iopscience.iop.org/1367-2630/9/5/133/pdf/1367-2630\_9\_5\_133.pdf
ER -
TY - JOUR
T1 - Ultracold atomic gases in optical lattices: mimicking condensed matter physics and beyond
JF - Advances in Physics
Y1 - 2007
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
A1 - Ahufinger, Veronica
A1 - Damski, B.
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
KW - optical lattices
VL - 56
UR - http://www.informaworld.com/smpp/ftinterface\~content=a778175433\~fulltext=713240930
ER -
TY - JOUR
T1 - Dynamics of F = 1 [sup 87]Rb condensates at finite temperatures
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2006
A1 - Mur-Petit, J.
A1 - Guilleumas, M.
A1 - Polls, Artur
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
A1 - Bongs, K.
A1 - Sengstock, K.
KW - atom optics
KW - atom-photon collisions
KW - Bose-Einstein condensation
KW - radiation pressure
KW - rubidium
KW - spin dynamics
KW - vectors
VL - 73
UR - http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PLRAAN000073000001013629000001&idtype=cvips&gifs=yes
ER -
TY - JOUR
T1 - Quantum-information processing in disordered and complex quantum systems
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2006
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Ahufinger, Veronica
A1 - Briegel, Hans J.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
KW - information theory
KW - quantum entanglement
KW - quantum gates
KW - radiation pressure
VL - 74
UR - http://link.aps.org/abstract/PRA/v74/e062309
ER -
TY - JOUR
T1 - Splitting and merging an elongated Bose-Einstein condensate at finite temperature
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2006
A1 - Mebrahtu, A.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
KW - Bose-Einstein condensation
KW - critical points
KW - fluctuations
VL - 73
UR - http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PLRAAN000073000003033601000001&idtype=cvips&gifs=yes
ER -
TY - JOUR
T1 - Strongly correlated Fermi-Bose mixtures in disordered optical lattices
JF - JOURNAL OF PHYSICS-LONDON-B ATOMIC MOLECULAR AND OPTICAL PHYSICS
Y1 - 2006
A1 - Sanchez-Palencia, L.
A1 - Ahufinger, Veronica
A1 - Kantian, A.
A1 - Zakrzewski, J.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
KW - optical lattices
VL - 39
UR - http://iopscience.iop.org/0953-4075/39/10/S12/pdf/0953-4075\_39\_10\_S12.pdf
ER -
TY - JOUR
T1 - Unitarity as Preservation of Entropy and Entanglement in Quantum Systems
JF - Foundations of Physics
Y1 - 2006
A1 - Hulpke, Florian
A1 - Poulsen, Uffe
A1 - Sanpera, Anna
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Lewenstein, Maciej
AB - Abstract The logical structure of Quantum Mechanics (QM) and its relation to other fundamental principles of Nature has been for decades a subject of intensive research. In particular, the question whether the dynamical axiom of QM can be derived from other principles has been often considered. In this contribution, we show that unitary evolutions arise as a consequences of demanding preservation of entropy in the evolution of a single pure quantum system, and preservation of entanglement in the evolution of composite quantum systems. 6
VL - 36
UR - http://www.springerlink.com/content/tjg6r668u462848r/fulltext.pdf
ER -
TY - JOUR
T1 - Continuous Variable Solution for Byzantine Agreement
JF - arXiv
Y1 - 2005
A1 - Neigovzen, Rodion
A1 - Sanpera, Anna
UR - http://arxiv.org/abs/quant-ph/0507249
ER -
TY - CONF
T1 - Disordered complex systems using cold gases and trapped ions
T2 - Laser Spectroscopy: Proceedings of the XVII International Conference, Aviemore, Scotland UK, 19-24 June 2005
Y1 - 2005
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Lewenstein, Maciej
A1 - Ahufinger, Veronica
A1 - Pons, Marisa
A1 - Sanpera, Anna
ED - Hinds, E. A.
ED - Ferguson, A.
ED - Riis, E.
JF - Laser Spectroscopy: Proceedings of the XVII International Conference, Aviemore, Scotland UK, 19-24 June 2005
PB - World Scientific
CY - Singapore
UR - http://arxiv.org/abs/quant-ph/0508018
ER -
TY - JOUR
T1 - Disordered ultracold atomic gases in optical lattices: A case study of Fermi-Bose mixtures
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2005
A1 - Ahufinger, Veronica
A1 - Sanchez-Palencia, L.
A1 - Kantian, A.
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
AB - We present a review of properties of ultracold atomic Fermi-Bose mixtures in inhomogeneous and random optical lattices. In the strong interacting limit and at very low temperatures, fermions form, together with bosons or bosonic holes, composite fermions. Composite fermions behave as a spinless interacting Fermi gas, and in the presence of local disorder they interact via random couplings and feel effective random local potential. This opens a wide variety of possibilities of realizing various kinds of ultracold quantum disordered systems. In this paper we review these possibilities, discuss the accessible quantum disordered phases, and methods for their detection. The discussed quantum phases include Fermi glasses, quantum spin glasses, “dirty” superfluids, disordered metallic phases, and phases involving quantum percolation.
PB - American Physical Society
VL - 72
UR - http://link.aps.org/doi/10.1103/PhysRevA.72.063616
ER -
TY - JOUR
T1 - Lattice Solitons in Quasicondensates
JF - Physical Review Letters
Y1 - 2005
A1 - Ahufinger, Veronica
A1 - Sanpera, Anna
AB - We analyze finite temperature effects in the generation of bright solitons in condensates in optical lattices. We show that even in the presence of strong phase fluctuations solitonic structures with a well defined phase profile can be created. We propose a novel family of variational functions which describe well the properties of these solitons and account for the nonlinear effects in the band structure. We discuss also the mobility and collisions of these localized wave packets.
PB - American Physical Society
VL - 94
UR - http://link.aps.org/doi/10.1103/PhysRevLett.94.130403
ER -
TY - JOUR
T1 - Quantum Key Distillation from Gaussian States by Gaussian Operations
JF - Physical Review Letters
Y1 - 2005
A1 - Navascués, M.
A1 - Bae, J.
A1 - Cirac, J. Ignacio
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
A1 - Acín, Antonio
AB - We study the secrecy properties of Gaussian states under Gaussian operations. Although such operations are useless for quantum distillation, we prove that it is possible to distill a secret key secure against any attack from sufficiently entangled Gaussian states with nonpositive partial transposition. Moreover, all such states allow for key distillation, when Eve is assumed to perform finite-size coherent attacks before the reconciliation process.
PB - American Physical Society
VL - 94
UR - http://link.aps.org/doi/10.1103/PhysRevLett.94.010502
ER -
TY - CHAP
T1 - The separability versus entanglement problem
T2 - Lectures on Quantum Information
Y1 - 2005
A1 - Sen(De), Aditi
A1 - Sen, Ujjwal
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
ED - Bruss, Dagmar
ED - Leuchs, G.
JF - Lectures on Quantum Information
PB - Wiley
SN - 9783527405275
UR - http://www3.wileyinterscience.com/cgi-bin/bookhome/117903246?CRETRY=1&SRETRY=0
ER -
TY - JOUR
T1 - Creation and mobility of discrete solitons in Bose-Einstein condensates
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2004
A1 - Ahufinger, Veronica
A1 - Sanpera, Anna
A1 - Pedri, P.
A1 - Santos, L.
A1 - Lewenstein, Maciej
AB - We analyze the generation and mobility of discrete solitons in Bose-Einstein condensates confined in an optical lattice under realistic experimental conditions. We discuss first the creation of one-dimensional discrete solitons, for both attractive and repulsive interatomic interactions. We then address the issue of their mobility, focusing our attention on the conditions for the experimental observability of the Peierls-Nabarro barrier. Finally we report on the generation of self-trapped structures in two and three dimensions. Discrete solitons may open alternative routes for the manipulation and transport of Bose-Einstein condensates.
PB - American Physical Society
VL - 69
UR - http://link.aps.org/doi/10.1103/PhysRevA.69.053604
ER -
TY - JOUR
T1 - Experimental Detection of Multipartite Entanglement using Witness Operators
JF - Physical Review Letters
Y1 - 2004
A1 - Bourennane, Mohamed
A1 - Eibl, Manfred
A1 - Kurtsiefer, Christian
A1 - Gaertner, Sascha
A1 - Weinfurter, Harald
A1 - Gühne, Otfried
A1 - Hyllus, Philipp
A1 - Bruß, Dagmar
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
VL - 92
UR - http://prl.aps.org/abstract/PRL/v92/i8/e087902
ER -
TY - JOUR
T1 - Simplifying Schmidt number witnesses via higher-dimensional embeddings
JF - Quantum Information and Computation
Y1 - 2004
A1 - Hulpke, F.
A1 - Bruss, Dagmar
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
VL - 4
ER -
TY - JOUR
T1 - Soliton Eigenvalue Control in Optical Lattices
JF - Physical Review Letters
Y1 - 2004
A1 - Kartashov, Yaroslav
A1 - Crasovan, Lucian-Cornel
A1 - Zelenina, Anna
A1 - Vysloukh, Victor
A1 - Sanpera, Anna
A1 - Lewenstein, Maciej
A1 - Torner, Lluis
VL - 93
UR - http://prl.aps.org/abstract/PRL/v93/i14/e143902
ER -
TY - CHAP
T1 - Entanglement properties of composite quantum systems
T2 - Quantum Information Processing
Y1 - 2003
A1 - Eckert, Kai
A1 - Guhne, O.
A1 - Hulpke, Florian
A1 - Hyllus, Philipp
A1 - Korbicz, J.
A1 - Mompart, Jordi
A1 - Bruss, Dagmar
A1 - Lewenstein, Maciej
A1 - Sanpera, Anna
ED - Leuchs, G.
ED - Beth, T.
JF - Quantum Information Processing
PB - Wilew-VCH
CY - Berlin
SN - 352740371X
ER -
TY - JOUR
T1 - Experimental detection of entanglement via witness operators and local measurements
JF - Journal of Modern Optics
Y1 - 2003
A1 - Gühne, Otfried
A1 - Hyllus, Philipp
A1 - Bruss, Dagmar
A1 - Ekert, Artur K.
A1 - Lewenstein, Maciej
A1 - Macchiavello, Chiara
A1 - Sanpera, Anna
VL - 50
UR - http://www.informaworld.com/smpp/36433790-99697256/content\~{}db=all\~{}content=a713826204
ER -
TY - JOUR
T1 - Schmidt-number witnesses and bound entanglement
JF - Physical Review A
Y1 - 2001
A1 - Sanpera, Anna
A1 - Bruß, Dagmar
A1 - Lewenstein, Maciej
VL - 63
UR - http://pra.aps.org/abstract/PRA/v63/i5/e050301
ER -
TY - JOUR
T1 - Separability and distillability in composite quantum systems - a primer
JF - Journal of Modern Optics
Y1 - 2000
A1 - Lewenstein, Maciej
A1 - Bruß, Dagmar
A1 - Cirac, J. Ignacio
A1 - Kraus, Barbara
A1 - Kuś, M.
A1 - Samsonowicz, J.
A1 - Sanpera, Anna
A1 - Tarrach, R.
VL - 47
UR - http://www.informaworld.com/smpp/6084610-44811133/content\~{}db=all\~{}content=a755833577
ER -