Spatially resolving two incoherent point sources whose separation is well below the diffraction limit dictated by classical optics has recently been shown possible using techniques that decompose the incoming radiation into orthogonal transverse modes. Such a demultiplexing procedure, however, must be perfectly calibrated to the transverse profile of the incoming light as any misalignment of the modes effectively restores the diffraction limit for small source separations. We study by how much can one mitigate such an effect at the level of measurement which, after being imperfectly demultiplexed due to inevitable misalignment, may still be partially corrected by linearly transforming the relevant dominating transverse modes. We consider two complementary tasks: the estimation of the separation between the two sources and the discrimination between one and two incoherent point sources. We show that, although one cannot fully restore super-resolving powers even when the value of the misalignment is perfectly known its negative impact on the ultimate sensitivity can be significantly reduced. In the case of estimation we analytically determine the exact relation between the minimal resolvable separation as a function of misalignment whereas for discrimination we analytically determine the relation between misalignment and the probability of error, as well as numerically determine how the latter scales in the limit of long interrogation times.

VL - 103 UR - https://link.aps.org/doi/10.1103/PhysRevA.103.022406http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.103.022406/fulltexthttps://link.aps.org/article/10.1103/PhysRevA.103.022406 JO - Phys. Rev. A ER - TY - JOUR T1 - Distributed Compression of Correlated Classical-Quantum Sources or: The Price of Ignorance JF - IEEE Transactions on Information Theory Y1 - 2020 A1 - Baghali Khanian, Zahra A1 - Winter, Andreas VL - 66 UR - https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=18https://ieeexplore.ieee.org/document/9039682/http://xplorestaging.ieee.org/ielx7/18/9170933/09039682.pdf?arnumber=9039682 JO - IEEE Trans. Inform. Theory ER - TY - JOUR T1 - Fundamental limits on key rates in device-independent quantum key distribution JF - New Journal of Physics Y1 - 2020 A1 - Eneet Kaur A1 - Mark M Wilde A1 - Andreas Winter AB -In this paper, we introduce intrinsic non-locality and quantum intrinsic non-locality as quantifiers for Bell non-locality, and we prove that they satisfy certain desirable properties such as faithfulness, convexity, and monotonicity under local operations and shared randomness. We then prove that intrinsic non-locality is an upper bound on the secret-key-agreement capacity of any device-independent protocol conducted using a device characterized by a correlation p, while quantum intrinsic non-locality is an upper bound on the same capacity for a correlation arising from an underlying quantum model. We also prove that intrinsic steerability is faithful, and it is an upper bound on the secret-key-agreement capacity of any one-sided-device-independent protocol conducted using a device characterized by an assemblage . Finally, we prove that quantum intrinsic non-locality is bounded from above by intrinsic steerability.

VL - 22 UR - https://doi.org/10.1088/1367-2630/ab6eaa ER - 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 - CONF T1 - Quantum State Redistribution for Ensemble Sources 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/9173935/http://xplorestaging.ieee.org/ielx7/9166581/9173928/09173935.pdf?arnumber=9173935 ER - TY - CONF T1 - Distributed Compression of Correlated Classical-Quantum Sources T2 - 2019 IEEE International Symposium on Information Theory (ISIT)2019 IEEE International Symposium on Information Theory (ISIT) Y1 - 2019 A1 - Khanian, Zahra Baghali A1 - Winter, Andreas JF - 2019 IEEE International Symposium on Information Theory (ISIT)2019 IEEE International Symposium on Information Theory (ISIT) PB - IEEE CY - Paris, France UR - https://ieeexplore.ieee.org/document/8849794/http://xplorestaging.ieee.org/ielx7/8827389/8849208/08849794.pdf?arnumber=8849794 ER - TY - CONF T1 - Entanglement-Assisted Quantum Data Compression T2 - 2019 IEEE International Symposium on Information Theory (ISIT)2019 IEEE International Symposium on Information Theory (ISIT) Y1 - 2019 A1 - Khanian, Zahra Baghali A1 - Winter, Andreas JF - 2019 IEEE International Symposium on Information Theory (ISIT)2019 IEEE International Symposium on Information Theory (ISIT) PB - IEEE CY - Paris, France UR - https://ieeexplore.ieee.org/document/8849352/http://xplorestaging.ieee.org/ielx7/8827389/8849208/08849352.pdf?arnumber=8849352 ER - TY - JOUR T1 - Extendibility Limits the Performance of Quantum Processors JF - Physical Review Letters Y1 - 2019 A1 - Kaur, Eneet A1 - Das, Siddhartha A1 - Wilde, Mark M. A1 - Winter, Andreas VL - 123 UR - https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.070502 JO - Phys. Rev. Lett. ER - TY - JOUR T1 - Extendibility Limits the Performance of Quantum Processors JF - Phys. Rev. Lett. Y1 - 2019 A1 - Kaur, Eneet A1 - Das, Siddhartha A1 - Wilde, Mark M. A1 - Winter, Andreas VL - 123 UR - https://link.aps.org/doi/10.1103/PhysRevLett.123.070502 ER - TY - JOUR T1 - Stochastic thermodynamics of self-oscillations: the electron shuttle JF - New J. Phys. Y1 - 2019 A1 - C. W. Wächtler A1 - P. Strasberg A1 - S. H. L. Klapp A1 - G. Schaller A1 - C. Jarzynski VL - 21 UR - https://iopscience.iop.org/article/10.1088/1367-2630/ab2727 ER - TY - JOUR T1 - Thermodynamics as a Consequence of Information Conservation JF - Quantum Y1 - 2019 A1 - Bera, Manabendra Nath A1 - Riera, Arnau A1 - Lewenstein, Maciej A1 - Khanian, Zahra Baghali A1 - Winter, Andreas VL - 3 UR - https://quantum-journal.orghttps://quantum-journal.org/papers/q-2019-02-14-121/https://quantum-journal.org/papers/q-2019-02-14-121/pdf/ JO - Quantum ER - TY - JOUR T1 - Bound entangled states fit for robust experimental verification JF - Quantum Y1 - 2018 A1 - Sentís, Gael A1 - Greiner, Johannes N. A1 - Shang, Jiangwei A1 - Siewert, Jens A1 - Kleinmann, Matthias VL - 2 UR - https://quantum-journal.orghttps://quantum-journal.org/papers/q-2018-12-18-113/https://quantum-journal.org/papers/q-2018-12-18-113/pdf/ JO - Quantum ER - TY - JOUR T1 - Experimentally detecting a quantum change point via the Bayesian inference JF - Physical Review A Y1 - 2018 A1 - Yu, Shang A1 - Huang, Chang-Jiang A1 - Tang, Jian-Shun A1 - Jia, Zhih-Ahn A1 - Wang, Yi-Tao A1 - Ke, Zhi-Jin A1 - Liu, Wei A1 - Liu, Xiao A1 - Zhou, Zong-Quan A1 - Cheng, Ze-Di A1 - Xu, Jin-Shi A1 - Wu, Yu-Chun A1 - Zhao, Yuan-Yuan A1 - Xiang, Guo-Yong A1 - Li, Chuan-Feng A1 - Guo, Guang-Can A1 - Sentís, Gael A1 - Muñoz-Tapia, Ramon VL - 98 UR - https://link.aps.org/doi/10.1103/PhysRevA.98.040301http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.98.040301/fulltexthttps://link.aps.org/article/10.1103/PhysRevA.98.040301 JO - Phys. Rev. A ER - TY - JOUR T1 - Measurements in two bases are sufficient for certifying high-dimensional entanglement JF - Nature Physics Y1 - 2018 A1 - Bavaresco, Jessica A1 - Herrera Valencia, Natalia A1 - Klockl, Claude A1 - Pivoluska, Matej A1 - Erker, Paul A1 - Friis, Nicolai A1 - Malik, Mehul A1 - Huber, Marcus VL - 14 UR - http://www.nature.com/articles/s41567-018-0203-zhttp://www.nature.com/articles/s41567-018-0203-z.pdfhttp://www.nature.com/articles/s41567-018-0203-zhttp://www.nature.com/articles/s41567-018-0203-z.pdf JO - Nature Phys ER - TY - JOUR T1 - Efficient Quantum Pseudorandomness with Nearly Time-Independent Hamiltonian Dynamics JF - PHYSICAL REVIEW X Y1 - 2017 A1 - Nakata, Yoshifumi A1 - Hirche, Christoph A1 - Koashi, Masato A1 - Winter, Andreas AB -Quantum randomness is an essential key to understanding the dynamics of complex many-body systems and also a powerful tool for quantum engineering. However, exact realizations of quantum randomness take an extremely long time and are infeasible in many-body systems, leading to the notion of quantum pseudorandomness, also known as unitary designs. Here, to explore microscopic dynamics of generating quantum pseudorandomness in many-body systems, we provide new efficient constructions of unitary designs and propose a design Hamiltonian, a random Hamiltonian of which dynamics always forms a unitary design after a threshold time. The new constructions are based on the alternate applications of random potentials in the generalized position and momentum spaces, and we provide explicit quantum circuits generating quantum pseudorandomness significantly more efficient than previous ones. We then provide a design Hamiltonian in disordered systems with periodically changing spin-glass-type interactions. The design Hamiltonian generates quantum pseudorandomness in a constant time even in the system composed of a large number of spins. We also point out the close relationship between the design Hamiltonian and quantum chaos.

VL - 7 ER - TY - JOUR T1 - Quantifying high dimensional entanglement with two mutually unbiased bases JF - Quantum Y1 - 2017 A1 - Erker, Paul A1 - Krenn, Mario A1 - Huber, Marcus AB - Paul Erker, Mario Krenn, and Marcus Huber, Quantum 1, 22 (2017). https://doi.org/10.22331/q-2017-07-28-22 We derive a framework for quantifying entanglement in multipartite and high dimensional systems using only correlations in two unbiased bases. We furthermore develop such bounds in cases whe… VL - 1 UR - https://quantum-journal.org/papers/q-2017-07-28-22/ ER - TY - JOUR T1 - Quantum metrology with full and fast quantum control JF - Quantum Y1 - 2017 A1 - Sekatski, Pavel A1 - Skotiniotis, Michalis A1 - Kołodyński, Janek A1 - Dür, Wolfgang AB - Pavel Sekatski, Michalis Skotiniotis, Janek Kołodyński, and Wolfgang Dür, Quantum 1, 27 (2017). https://doi.org/10.22331/q-2017-09-06-27 We establish general limits on how precise a parameter, e.g. frequency or the strength of a magnetic field, can be estimated with the aid of full and fast quantum control. We consider uncorr… VL - 1 UR - https://quantum-journal.org/papers/q-2017-09-06-27/ ER - TY - JOUR T1 - Classical capacities of quantum channels with environment assistance JF - Problems of Information Transmission Y1 - 2016 A1 - Karumanchi, S. A1 - Mancini, S. A1 - Winter, A. A1 - Yang, D. AB - A quantum channel physically is a unitary interaction between an information carrying system and an environment, which is initialized in a pure state before the interaction. Conventionally, this state, as also the parameters of the interaction, is assumed to be fixed and known to the sender and receiver. Here, following the model introduced by us earlier [1], we consider a benevolent third party, i.e., a helper, controlling the environment state, and show how the helper’s presence changes the communication game. In particular, we define and study the classical capacity of a unitary interaction with helper, in two variants: one where the helper can only prepare separable states across many channel uses, and one without this restriction. Furthermore, two even more powerful scenarios of pre-shared entanglement between helper and receiver, and of classical communication between sender and helper (making them conferencing encoders) are considered. VL - 52 UR - https://link.springer.com/article/10.1134/S0032946016030029 ER - TY - JOUR T1 - Compressed quantum metrology for the Ising Hamiltonian JF - Physical Review A Y1 - 2016 A1 - Boyajian, W. L. A1 - Skotiniotis, M. A1 - Dür, W. A1 - Kraus, B. VL - 94 UR - https://link.aps.org/doi/10.1103/PhysRevA.94.062326http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.94.062326/fulltexthttp://link.aps.org/article/10.1103/PhysRevA.94.062326 JO - Phys. Rev. A ER - TY - JOUR T1 - Heisenberg-{Weyl} {Observables}: {Bloch} vectors in phase space JF - Physical Review A Y1 - 2016 A1 - Asadian, Ali A1 - Erker, Paul A1 - Huber, Marcus A1 - Klockl, Claude AB - We introduce a Hermitian generalization of Pauli matrices to higher dimensions which is based on Heisenberg-Weyl operators. The complete set of Heisenberg-Weyl observables allows us to identify a real-valued Bloch vector for an arbitrary density operator in discrete phase space, with a smooth transition to infinite dimensions. Furthermore, we derive bounds on the sum of expectation values of any set of anticommuting observables. Such bounds can be used in entanglement detection and we show that Heisenberg-Weyl observables provide a first nontrivial example beyond the dichotomic case. VL - 94 UR - https://link.aps.org/doi/10.1103/PhysRevA.94.010301 ER - TY - JOUR T1 - Multi-photon entanglement in high dimensions JF - Nature Photonics Y1 - 2016 A1 - Malik, Mehul A1 - Erhard, Manuel A1 - Huber, Marcus A1 - Krenn, Mario A1 - Robert Fickler A1 - Anton Zeilinger PB - Nature Publishing Group VL - 10 SN - 1749-4885 UR - http://dx.doi.org/10.1038/nphoton.2016.12 IS - 4 ER - TY - JOUR T1 - Quantum Channel Capacities With Passive Environment Assistance JF - IEEE Transactions on Information Theory Y1 - 2016 A1 - Karumanchi, Siddharth A1 - Mancini, Stefano A1 - Winter, Andreas A1 - Dong Yang VL - 62 IS - 4 JO - IEEE Trans. Inform. Theory ER - TY - JOUR T1 - Witnessing entanglement by proxy JF - New Journal of Physics Y1 - 2016 A1 - Bäuml, Stefan A1 - Bruß, Dagmar A1 - Huber, Marcus A1 - Kampermann, Hermann A1 - Winter, Andreas VL - 18 IS - 1 JO - New J. Phys. ER - TY - JOUR T1 - Characterizing multipartite entanglement without shared reference frames JF - Physical Review A Y1 - 2015 A1 - Klöckl, C. A1 - Huber, M VL - 91 UR - http://link.aps.org/doi/10.1103/PhysRevA.91.042339 ER - TY - JOUR T1 - Thermodynamic cost of creating correlations JF - New Journal of Physics Y1 - 2015 A1 - Huber, Marcus A1 - Martí Perarnau-Llobet A1 - Karen V. Hovhannisyan A1 - Paul Skrzypczyk A1 - Klöckl, Claude A1 - Nicolas Brunner A1 - Acín, Antonio VL - 17 UR - http://stacks.iop.org/1367-2630/17/i=6/a=065008?key=crossref.b9c20f4bb628b09efcb912347c01851e ER - TY - JOUR T1 - Thermodynamic cost of creating correlations JF - New Journal of Physics Y1 - 2015 A1 - Huber, Marcus A1 - Perarnau-Llobet, Marti A1 - Hovhannisyan, Karen V A1 - Skrzypczyk, Paul A1 - Klockl, Claude A1 - Brunner, Nicolas A1 - Acín, Antonio VL - 17 UR - https://iopscience.iop.org/article/10.1088/1367-2630/17/6/065008 JO - New J. Phys. 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 - Entangled singularity patterns of photons in {Ince}-{Gauss} modes JF - Physical Review A Y1 - 2013 A1 - Krenn, Mario A1 - Robert Fickler A1 - Huber, Marcus A1 - Radek Lapkiewicz A1 - Plick, William A1 - Ramelow, Sven A1 - Anton Zeilinger VL - 87 UR - http://link.aps.org/doi/10.1103/PhysRevA.87.012326 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 - Entangling two distant oscillators with a quantum reservoir JF - EPL (Europhysics Letters) Y1 - 2011 A1 - Wolf, A A1 - De Chiara, G. A1 - Kajari, E A1 - Lutz, E A1 - G. Morigi AB - The generation of entanglement between two oscillators that interact via a common reservoir is theoretically studied. The reservoir is modeled by a one-dimensional harmonic crystal initially in thermal equilibrium. Starting from a separable state, the oscillators can become entangled after a transient time, that is of the order of the thermalization time scale. This behaviour is observed at finite temperature even when the oscillators are at a distance significantly larger than the crystal's interparticle spacing. The underlying physical mechanisms can be explained by the dynamical properties of the collective variables of the two oscillators which may decouple from or be squeezed by the reservoir. Our predictions can be tested with an ion chain in a linear Paul trap. VL - 95 UR - http://epljournal.edpsciences.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/epl/abs/2011/18/epl13816/epl13816.html IS - 6 JO - EPL ER - TY - JOUR T1 - Topological superfluids on a lattice with non-Abelian gauge fields JF - Europhysics Letters Y1 - 2010 A1 - A. Kubasiak A1 - Massignan, P. A1 - Lewenstein, M. VL - 92 UR - http://arxiv.org/abs/1007.4827 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 - 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 - Atomic Fermi-Bose Mixtures in Inhomogeneous and Random Lattices: From Fermi Glass to Quantum Spin Glass and Quantum Percolation JF - Physical Review Letters Y1 - 2004 A1 - Sanpera, A. A1 - Kantian, A. A1 - Sanchez-Palencia, L. A1 - Zakrzewski, J. A1 - Lewenstein, M. VL - 93 UR - http://prl.aps.org/abstract/PRL/v93/i4/e040401 ER - TY - JOUR T1 - Coherence Properties of Guided-Atom Interferometers JF - Physical Review Letters Y1 - 2004 A1 - Kreutzmann, H. A1 - Poulsen, U. A1 - Lewenstein, M. A1 - Dumke, R. A1 - Ertmer, W. A1 - Birkl, G. A1 - Sanpera, A. VL - 92 UR - http://prl.aps.org/abstract/PRL/v92/i16/e163201 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 - 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 - Feynman's path-integral approach for intense-laser-atom interactions JF - Science (New York, N.Y.) Y1 - 2001 A1 - Salieres, P. A1 - Carre, B. A1 - Le Deroff, L. A1 - Grasbon, F. A1 - Paulus, G. G. A1 - Walther, H. A1 - Kopold, R. A1 - Becker, W. A1 - Milosevic, D. B. A1 - Sanpera, A. A1 - Lewenstein, M. AB - Atoms interacting with intense laser fields can emit electrons and photons of very high energies. An intuitive and quantitative explanation of these highly nonlinear processes can be found in terms of a generalization of classical Newtonian particle trajectories, the so-called quantum orbits. Very few quantum orbits are necessary to reproduce the experimental results. These orbits are clearly identified, thus opening the way for an efficient control as well as previously unknown applications of these processes. VL - 292 UR - http://www.sciencemag.org/cgi/content/abstract/292/5518/902 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 -