We show that the distillable coherence-which is equal to the relative entropy of coherence-is, up to a constant factor, always bounded by the l(1)-norm measure of coherence (defined as the sum of absolute values of off diagonals). Thus the latter plays a similar role as logarithmic negativity plays in entanglement theory and this is the best operational interpretation from a resource-theoretic viewpoint. Consequently the two measures are intimately connected to another operational measure, the robustness of coherence. We find also relationships between these measures, which are tight for general states, and the tightest possible for pure and qubit states. For a given robustness, we construct a state having minimum distillable coherence.

VL - 96 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 - 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 - Bell Inequalities with No Quantum Violation and Unextendable Product Bases JF - Phys. Rev. Lett. Y1 - 2011 A1 - Remigiusz Augusiak A1 - Julia Stasińska A1 - Hadley, Christopher A1 - Korbicz, Jarosław K. A1 - Lewenstein, Maciej A1 - Acín, Antonio AB - The strength of classical correlations is subject to certain constraints, commonly known as Bell inequalities. Violation of these inequalities is the manifestation of nonlocality—displayed, in particular, by quantum mechanics, meaning that quantum mechanics can outperform classical physics at tasks associated with such Bell inequalities. Interestingly, however, there exist situations in which this is not the case. We associate an intriguing class of bound entangled states, constructed from unextendable product bases with a wide family of tasks, for which (i) quantum correlations do not outperform the classical ones but (ii) there exist supraquantum nonsignaling correlations that do provide an advantage. PB - American Physical Society VL - 107 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 - 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 - 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 - 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 - Cold Atoms in Non-Abelian Gauge Potentials: From the Hofstadter "Moth" to Lattice Gauge Theory JF - Physical Review Letters Y1 - 2005 A1 - Osterloh, K. A1 - Baig, Marià A1 - Santos, L. A1 - Zoller, P. A1 - Lewenstein, Maciej AB - We demonstrate how to create artificial external non-Abelian gauge potentials acting on cold atoms in optical lattices. The method employs atoms with k internal states, and laser assisted state sensitive tunneling, described by unitary k×k matrices. The single-particle dynamics in the case of intense U(2) vector potentials lead to a generalized Hofstadter butterfly spectrum which shows a complex mothlike structure. We discuss the possibility to realize non-Abelian interferometry (Aharonov-Bohm effect) and to study many-body dynamics of ultracold matter in external lattice gauge fields. PB - American Physical Society VL - 95 UR - http://link.aps.org/doi/10.1103/PhysRevLett.95.010403 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 - 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 - TY - JOUR T1 - {Generalized laws of thermodynamics in the presence of correlations} JF - {NATURE COMMUNICATIONS} Y1 - 0 A1 - Bera, Manabendra N. A1 - Riera, Arnau A1 - Lewenstein, Maciej A1 - Winter, Andreas AB - {The laws of thermodynamics, despite their wide range of applicability, are known to break down when systems are correlated with their environments. Here we generalize thermodynamics to physical scenarios which allow presence of correlations, including those where strong correlations are present. We exploit the connection between information and physics, and introduce a consistent redefinition of heat dissipation by systematically accounting for the information flow from system to bath in terms of the conditional entropy. As a consequence, the formula for the Helmholtz free energy is accordingly modified. Such a remedy not only fixes the apparent violations of Landauer's erasure principle and the second law due to anomalous heat flows, but also leads to a generally valid reformulation of the laws of thermodynamics. In this information-theoretic approach, correlations between system and environment store work potential. Thus, in this view, the apparent anomalous heat flows are the refrigeration processes driven by such potentials.} VL - {8} ER -