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Related papers: Quantum Metrology: Dynamics vs. Entanglement

200 papers

We show that a von Neumann measurement on a part of a composite quantum system unavoidably creates distillable entanglement between the measurement apparatus and the system if the state has nonzero quantum discord. The minimal distillable…

Quantum Physics · Physics 2011-05-03 Alexander Streltsov , Hermann Kampermann , Dagmar Bruß

Measuring entanglement is a demanding task that usually requires full tomography of a quantum system, involving a number of observables that grows exponentially with the number of parties. Recently, it was suggested that adding a single…

We generalize previously proposed conditions each measure of entanglement has to satisfy. We present a class of entanglement measures that satisfy these conditions and show that the Quantum Relative Entropy and Bures Metric generate two…

Quantum Physics · Physics 2011-07-19 V. Vedral , M. B. Plenio

Quantum correlations between parts of a composite system most clearly reveal themselves through entanglement. Designing, maintaining, and controlling entangled systems is very demanding, which raises the stakes for understanding the…

Quantum Physics · Physics 2019-08-21 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

A model of quantum measurement is proposed, which aims to describe statistical mechanical aspects of this phenomenon, starting from a purely Hamiltonian formulation. The macroscopic measurement apparatus is modeled as an ideal Bose gas, the…

Statistical Mechanics · Physics 2016-08-31 Armen E. Allahverdyan , Roger Balian , Theo M. Nieuwenhuizen

Using the Vakarchuk formulae for the density matrix, we calculate the number N_k of atoms with momentum \hbar k for the ground state of a uniform one-dimensional periodic system of interacting bosons. We obtain for impenetrable point bosons…

Quantum Gases · Physics 2016-06-01 Maksim Tomchenko

We discuss a general notion of quantum correlations in fermionic or bosonic indistinguishable particles. Our approach is mainly based on the identification of the algebra of single-particle observables, which allows us to devise an…

Quantum Physics · Physics 2014-03-18 Fernando Iemini , Tiago Debarba , Reinaldo O. Vianna

We reports direct and scalable measurement of multiparticle entanglement concurrence and three-tangle with embedding photonic quantum simulators. In this embedding framework [Phys. Rev. Lett. 111, 240502 (2013)], $N$-qubit entanglement…

Quantum Physics · Physics 2016-02-24 Ming-Cheng Chen , Dian Wu , Zu-En Su , Xin-Dong Cai , Xi-Lin Wang , Tao Yang , Li Li , Nai-Le Liu , Chao-Yang Lu , Jan-Wei Pan

An analysis of quantum measurement is presented that relies on an information-theoretic description of quantum entanglement. In a consistent quantum information theory of entanglement, entropies (uncertainties) conditional on measurement…

Quantum Physics · Physics 2008-02-03 N. J. Cerf , C. Adami

Quantum information theory and quantum computing are theoritical basis of quantum computers. Thanks to entanglement, quantum mechanical systems are provisioned to realize many information processing problems faster than classical…

Quantum Physics · Physics 2017-04-19 Volkan Erol

We consider a two-component Bose-Einstein condensate, which contains atoms with magnetic dipole moments aligned along the $z$ direction (labeled as component 1) and nonmagnetic atoms (labeled as component 2). The problem is studied by means…

Quantum Gases · Physics 2011-08-08 Kui-Tian Xi , Jinbin Li , Da-Ning Shi

A key lesson of the decoherence program is that information flowing out from an open system is stored in the quantum state of the surroundings. Simultaneously, quantum measurement theory shows that the evolution of any open system when its…

Quantum Physics · Physics 2012-01-27 Juan Diego Urbina , Walter T. Strunz , Carlos Viviescas

Electronic quantum entanglement between the central chain and the two electrodes in an infinite one-dimensional two-probe device system is studied. The entanglement entropy is calculated employing the nonequilibrium Green's function method…

Mesoscale and Nanoscale Physics · Physics 2016-03-02 Yao-Sheng Li , Wen-Long You , Xue-Feng Wang

We study the problem of rapid change of the interaction parameter (quench) in many-body low-dimensional system. It is shown that, measuring correlation functions after the quench the information about a spectrum of collective excitations in…

Other Condensed Matter · Physics 2011-11-09 Vladimir Gritsev , Eugene Demler , Mikhail Lukin , Anatoli Polkovnikov

We study the relaxation dynamics of quantum turbulence in a two-component Bose-Einstein condensate containing half-quantum vortices. We find a temporal scaling regime for the number of vortices and the correlation lengths that at early…

Quantum Gases · Physics 2021-10-07 M. T. Wheeler , H. Salman , M. O. Borgh

Two independently prepared condensates can be combined into a single larger condensate by detection of their relative phase in an intereference measurement.

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Klaus Molmer

We construct a variational wave function for the ground state of weakly interacting bosons that gives a lower energy than the mean-field Girardeau-Arnowitt (or Hartree-Fock-Bogoliubov) theory. This improvement is brought about by…

Quantum Gases · Physics 2017-03-16 Takafumi Kita

Issues related to quantum entanglement in systems of indistinguishable particles, as discussed in the information theoretic approach, are extended to anyonic statistics. Local and non-local measurements discussed in this framework are…

Quantum Physics · Physics 2021-10-28 Ramadas N , V V Sreedhar

We investigate the emergence of three-dimensional behavior in a reduced-dimension Bose-Einstein condensate trapped by a highly anisotropic potential. We handle the problem analytically by performing a perturbative Schmidt decomposition of…

Quantum Physics · Physics 2015-05-28 Alexandre B. Tacla , Carlton M. Caves

Characterizing many-body systems through the quantum correlations between their constituent particles is a major goal of quantum physics. Although entanglement is routinely observed in many systems, we report here the detection of stronger…