TY - JOUR
T1 - Indistinguishability-enabled coherence for quantum metrology
JF - Phys. Rev. A
Y1 - 2019
A1 - Castellini, Alessia
A1 - Lo Franco, Rosario
A1 - Lami, Ludovico
A1 - Winter, Andreas
A1 - Adesso, Gerardo
A1 - Compagno, Giuseppe
VL - 100
UR - https://link.aps.org/doi/10.1103/PhysRevA.100.012308
ER -
TY - JOUR
T1 - Feynman graphs and the large dimensional limit of multipartite entanglement
JF - Journal of Mathematical Physics
Y1 - 2018
A1 - Di Martino, Sara
A1 - Facchi, Paolo
A1 - Florio, Giuseppe
VL - 59
UR - http://aip.scitation.org/doi/10.1063/1.5019481http://aip.scitation.org/doi/pdf/10.1063/1.5019481
JO - Journal of Mathematical Physics
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 - Using and reusing coherence to realize quantum processes
JF - Quantum
Y1 - 2018
A1 - García-Díaz, María
A1 - Fang, Kun
A1 - Wang, Xin
A1 - Rosati, Matteo
A1 - Skotiniotis, Michalis
A1 - Calsamiglia, John
A1 - Winter, Andreas
VL - 2
UR - https://quantum-journal.orghttps://quantum-journal.org/papers/q-2018-10-19-100/https://quantum-journal.org/papers/q-2018-10-19-100/pdf/
JO - Quantum
ER -
TY - JOUR
T1 - Flexible resources for quantum metrology
JF - New Journal of Physics
Y1 - 2017
A1 - Friis, Nicolai
A1 - Orsucci, Davide
A1 - Skotiniotis, Michalis
A1 - Sekatski, Pavel
A1 - Dunjko, Vedran
A1 - Briegel, Hans J.
A1 - Dür, Wolfgang
AB - Quantum metrology offers a quadratic advantage over classical approaches to parameter estimation problems by utilising entanglement and nonclassicality. However, the hurdle of actually implementing the necessary quantum probe states and measurements, which vary drastically for different metrological scenarios, is usually not taken into account. We show that for a wide range of tasks in metrology, 2D cluster states (a particular family of states useful for measurement-based quantum computation) can serve as flexible resources that allow one to efficiently prepare any required state for sensing, and perform appropriate (entangled) measurements using only single qubit operations. Crucially, the overhead in the number of qubits is less than quadratic, thus preserving the quantum scaling advantage. This is ensured by using a compression to a logarithmically sized space that contains all relevant information for sensing. We specifically demonstrate how our method can be used to obtain optimal scaling for phase and frequency estimation in local estimation problems, as well as for the Bayesian equivalents with Gaussian priors of varying widths. Furthermore, we show that in the paradigmatic case of local phase estimation 1D cluster states are sufficient for optimal state preparation and measurement.
VL - 19
UR - http://stacks.iop.org/1367-2630/19/i=6/a=063044
ER -
TY - JOUR
T1 - Microcanonical and resource-theoretic derivations of the thermal state of a quantum system with noncommuting charges
JF - Nature Communications
Y1 - 2016
A1 - Yunger Halpern, Nicole
A1 - Faist, Philippe
A1 - Oppenheim, Jonathan
A1 - Winter, Andreas
VL - 77
UR - http://www.nature.com/doifinder/10.1038/ncomms12051
JO - Nat Comms
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 - Probabilistically Perfect Cloning of Two Pure States: Geometric Approach
JF - Physical Review Letters
Y1 - 2016
A1 - Yerokhin, V.
A1 - Shehu, A.
A1 - Feldman, E.
A1 - E. Bagan
A1 - Bergou, J. A.
VL - 116
IS - 20
JO - Phys. Rev. Lett.
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 - Thermodynamics of creating correlations: {Limitations} and optimal protocols
JF - Physical Review E
Y1 - 2015
A1 - Bruschi, David Edward
A1 - Martí Perarnau-Llobet
A1 - Friis, Nicolai
A1 - Karen V. Hovhannisyan
A1 - Huber, Marcus
VL - 91
UR - http://link.aps.org/doi/10.1103/PhysRevE.91.032118
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 - Interface between path and orbital angular momentum entanglement for high-dimensional photonic quantum information
JF - Nature Communications
Y1 - 2014
A1 - Robert Fickler
A1 - Radek Lapkiewicz
A1 - Huber, Marcus
A1 - Lavery, Martin P.J.
A1 - Padgett, Miles J.
A1 - Anton Zeilinger
AB - Photonics has become a mature field of quantum information science, where integrated optical circuits offer a way to scale the complexity of the setup as well as the dimensionality of the quantum state. On photonic chips, paths are the natural way to encode information. To distribute those high-dimensional quantum states over large distances, transverse spatial modes, like orbital angular momentum (OAM) possessing Laguerre Gauss modes, are favourable as flying information carriers. Here we demonstrate a quantum interface between these two vibrant photonic fields. We create three-dimensional path entanglement between two photons in a non-linear crystal and use a mode sorter as the quantum interface to transfer the entanglement to the OAM degree of freedom. Thus our results show a novel, flexible way to create high-dimensional spatial mode entanglement. Moreover, they pave the way to implement broad complex quantum networks where high-dimensionally entangled states could be distributed over distant photonic chips.
VL - 5
JO - Nat Comms
ER -
TY - Generic
T1 - Strong Converse for the Quantum Capacity of the Erasure Channel for Almost All Codes
T2 - 9th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2014)
Y1 - 2014
A1 - Wilde, Mark M.
A1 - Winter, Andreas
ED - Steve T Flammia
ED - Harrow, Aram W.
JF - 9th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2014)
PB - LIPICS
CY - Singapore
VL - 27
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 - THES
T1 - Entanglement percolation with graph-states'
T2 - Departament de Físca, Grup de Física Teòria: Informació i fenòmens quàntics
Y1 - 2012
A1 - Franquet, Abert
JF - Departament de Físca, Grup de Física Teòria: Informació i fenòmens quàntics
PB - Universitat Autònoma de Barcelona
CY - Barcelona
VL - Grau en Física
ER -
TY - JOUR
T1 - The quantum ground state of self-organized atomic crystals in optical resonators
JF - Phys. Rev. A
Y1 - 2010
A1 - S. Fernández-Vidal
A1 - De Chiara, Gabriele
A1 - J. Larson
A1 - G. Morigi
AB - Cold atoms, driven by a laser and simultaneously coupled to the quantum field of an optical resonator, may self-organize in periodic structures. These structures are supported by the optical lattice, which emerges from the laser light they scatter into the cavity mode and form when the laser intensity exceeds a threshold value. We study theoretically the quantum ground state of these structures above the pump threshold of self-organization by mapping the atomic dynamics of the self-organized crystal to a Bose-Hubbard model. We find that the quantum ground state of the self-organized structure can be the one of a Mott insulator, depending on the pump strength of the driving laser. For very large pump strengths, where the intracavity-field intensity is maximum and one would expect a Mott-insulator state, we find intervals of parameters where the phase is compressible. These states could be realized in existing experimental setups.
VL - 81
UR - http://link.aps.org/doi/10.1103/PhysRevA.81.043407
ER -
TY - JOUR
T1 - Quantum-limited metrology with product states
JF - Physical Review A (Atomic, Molecular, and Optical Physics)
Y1 - 2008
A1 - Boixo, Sergio
A1 - Datta, Animesh
A1 - Flammia, Steven T.
A1 - Shaji, Anil
A1 - Bagan, Emili
A1 - Caves, Carlton M.
KW - angular momentum theory
KW - Bose-Einstein condensation
KW - bound states
KW - protocols
KW - quantum entanglement
VL - 77
UR - http://link.aps.org/abstract/PRA/v77/e012317
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 - CHAP
T1 - Popper's test of Quantum Mechanics
T2 - Fundamental Physics Meeting "Alberto Galindo"
Y1 - 2004
A1 - Bramon, Albert
A1 - Escribano, Rafel
ED - Alvarez-Estrada, R. F.
ED - Dobado, A.
ED - Fernandez, L. A.
ED - Mart\'ın-Delgado, M. A.
ED - {Munoz Sudupe}, A.
JF - Fundamental Physics Meeting "Alberto Galindo"
PB - Aula Documental de Investigacion
CY - Madrid
UR - http://arxiv.org/abs/quant-ph/0501134
ER -