TY - CONF
T1 - General Mixed State Quantum Data Compression with and without Entanglement Assistance
T2 - 2020 IEEE International Symposium on Information Theory (ISIT)2020 IEEE International Symposium on Information Theory (ISIT)
Y1 - 2020
A1 - Khanian, Zahra Baghali
A1 - Winter, Andreas
JF - 2020 IEEE International Symposium on Information Theory (ISIT)2020 IEEE International Symposium on Information Theory (ISIT)
PB - IEEE
CY - Los Angeles, CA, USA
UR - https://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=9166581https://ieeexplore.ieee.org/document/9174148/http://xplorestaging.ieee.org/ielx7/9166581/9173928/09174148.pdf?arnumber=9174148
ER -
TY - JOUR
T1 - Gaussian quantum resource theories
JF - Physical Review A
Y1 - 2018
A1 - Lami, Ludovico
A1 - Regula, Bartosz
A1 - Wang, Xin
A1 - Nichols, Rosanna
A1 - Winter, Andreas
A1 - Adesso, Gerardo
VL - 987
UR - https://link.aps.org/doi/10.1103/PhysRevA.98.022335http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.98.022335/fulltexthttps://link.aps.org/article/10.1103/PhysRevA.98.022335
JO - Phys. Rev. A
ER -
TY - JOUR
T1 - A generalized wave-particle duality relation for finite groups
JF - Journal of Physics A: Mathematical and Theoretical
Y1 - 2018
A1 - Bagan, Emilio
A1 - John Calsamiglia
A1 - Bergou, János A
A1 - Hillery, Mark
VL - 51
JO - J. Phys. A: Math. Theor.
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 - Generalized laws of thermodynamics in the presence of correlations
JF - Nature Communications
Y1 - 2017
A1 - Bera, Manabendra N.
A1 - Riera, Arnau
A1 - Lewenstein, Maciej
A1 - Winter, Andreas
VL - 8
UR - http://www.nature.com/articles/s41467-017-02370-xhttp://www.nature.com/articles/s41467-017-02370-x.pdfhttp://www.nature.com/articles/s41467-017-02370-x.pdfhttp://www.nature.com/articles/s41467-017-02370-x
JO - Nat Commun
ER -
TY - JOUR
T1 - Genuine-multipartite entanglement criteria based on positive maps
JF - JOURNAL OF MATHEMATICAL PHYSICS
Y1 - 2017
A1 - Clivaz, Fabien
A1 - Huber, Marcus
A1 - Lami, Ludovico
A1 - Murta, Glaucia
AB - Positive maps applied to a subsystem of a bipartite quantum state constitute a central tool in characterising entanglement. In the multipartite case, however, the direct application of a positive but not completely positive map cannot distinguish if a state is genuinely multipartite entangled or just entangled across some bipartition. We thus generalise this bipartite concept to the multipartite setting by introducing non-positive maps that are positive on the subset of biseparable states but can map to a non-positive element if applied to a genuine multipartite entangled state. We explicitly construct examples of multipartite non-positive maps, obtained from positive maps via a lifting procedure, that in this fashion can reveal genuine multipartite entanglement in a robust way. Published by AIP Publishing.
VL - 58
ER -
TY - JOUR
T1 - Global and local thermometry schemes in coupled quantum systems
JF - NEW JOURNAL OF PHYSICS
Y1 - 2017
A1 - Campbell, Steve
A1 - Mehboudi, Mohammad
A1 - De Chiara, Gabriele
A1 - Paternostro, Mauro
AB - We study the ultimate bounds on the estimation of temperature for an interacting quantum system. We consider two coupled bosonic modes that are assumed to be thermal and using quantum estimation theory establish the role the Hamiltonian parameters play in thermometry. We show that in the case of a conserved particle number the interaction between the modes leads to a decrease in the overall sensitivity to temperature, while interestingly, if particle exchange is allowed with the thermal bath the converse is true. We explain this dichotomy by examining the energy spectra. Finally, we devise experimentally implementable thermometry schemes that rely only on locally accessible information from the total system, showing that almost Heisenberg limited precision can still be achieved, and we address the (im)possibility for multiparameter estimation in the system.
VL - 19
ER -
TY - JOUR
T1 - A geometric approach to quantum state separation
JF - New Journal of Physics
Y1 - 2015
A1 - E. Bagan
A1 - Yerokhin, V.
A1 - Shehu, A.
A1 - Feldman, E.
A1 - Bergou, J. A.
AB - Probabilistic quantum state transformations can be characterized by the degree of state separation they provide. This, in turn, sets limits on the success rate of these transformations. We consider optimum state separation of two known pure states in the general case where the known states have arbitrary a priori probabilities. The problem is formulated from a geometric perspective and shown to be equivalent to the problem of finding tangent curves within two families of conics that represent the unitarity constraints and the objective functions to be optimized, respectively. We present the corresponding analytical solutions in various forms. In the limit of perfect state separation, which is equivalent to unambiguous state discrimination, the solution exhibits a phenomenon analogous to a second order symmetry breaking phase transition. We also propose a linear optics implementation of separation which is based on the dual rail representation of qubits and single-photon multiport interferometry.
VL - 17
UR - http://stacks.iop.org/1367-2630/17/i=12/a=123015
ER -
TY - JOUR
T1 - Generation and confirmation of a (100 x 100)-dimensional entangled quantum system
JF - Proceedings of the National Academy of Sciences
Y1 - 2014
A1 - Krenn, M.
A1 - Huber, M
A1 - Fickler, R.
A1 - Lapkiewicz, R.
A1 - Ramelow, S.
A1 - Zeilinger, A.
AB - Entangled quantum systems have properties that have fundamentally overthrown the classical worldview. Increasing the complexity of entangled states by expanding their dimensionality allows the implementation of novel fundamental tests of nature, and moreover also enables genuinely new protocols for quantum information processing. Here we present the creation of a (100x100)-dimensional entangled quantum system, using spatial modes of photons. For its verification we develop a novel nonlinear criterion which infers entanglement dimensionality of a global state by using only information about its subspace correlations. This allows very practical experimental implementation as well as highly efficient extraction of entanglement dimensionality information. Applications in quantum cryptography and other protocols are very promising.
VL - 111
IS - 17
JO - Proceedings of the National Academy of Sciences
ER -
TY - JOUR
T1 - Graph-Theoretic Approach to Quantum Correlations
JF - Physical Review Letters
Y1 - 2014
A1 - Cabello, Adán
A1 - Severini, Simone
A1 - Winter, Andreas
VL - 112
IS - 4
JO - Phys. Rev. Lett.
ER -
TY - CONF
T1 - Graph-theoretical Bounds on the Entangled Value of Non-local Games
T2 - 9th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2014)
Y1 - 2014
A1 - Chailloux, André
A1 - Mančinska, Laura
A1 - Scarpa, Giannicola
A1 - Severini, Simone
ED - Flammia, Steven T.
ED - Harrow, Aram W.
JF - 9th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2014)
PB - Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik
CY - Dagstuhl, Germany
SN - 978-3-939897-73-6
UR - http://drops.dagstuhl.de/opus/volltexte/2014/4807
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 - Growth of graph states in quantum networks
JF - Physical Review A
Y1 - 2012
A1 - Cuquet, Martí
A1 - John Calsamiglia
AB - We propose a scheme to distribute graph states over quantum networks in the presence of noise in the channels and in the operations. The protocol can be implemented efficiently for large graph sates of arbitrary (complex) topology. We benchmark our scheme with two protocols where each connected component is prepared in a node belonging to the component and subsequently distributed via quantum repeaters to the remaining connected nodes. We show that the fidelity of the generated graphs can be written as the partition function of a classical Ising-type Hamiltonian. We give exact expressions of the fidelity of the linear cluster and results for its decay rate in random graphs with arbitrary (uncorrelated) degree distributions.
VL - 86
UR - http://link.aps.org/doi/10.1103/PhysRevA.86.042304
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 -