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QUROPE - aggregated feeds in category JournalsenPRA: Quantum information: Chiral spin currents in a trapped-ion quantum simulator using Floquet engineering
http://link.aps.org/doi/10.1103/PhysRevA.97.010302
<p>Author(s): Tobias Graß, Alessio Celi, Guido Pagano, and Maciej Lewenstein</p><p>The most typical ingredient of topologically protected quantum states is magnetic fluxes. In a system of spins, complex-valued interaction parameters give rise to a flux, if their phases do not add up to zero along a closed loop. Here we apply periodic driving, a powerful tool for quantum engineerin...</p><br/><p>[Phys. Rev. A 97, 010302(R)] Published Fri Jan 19, 2018</p>Fri, 19 Jan 2018 11:00:00 +0100PRA: Quantum information: Protecting the entanglement of twisted photons by adaptive optics
http://link.aps.org/doi/10.1103/PhysRevA.97.012321
<p>Author(s): Nina Leonhard, Giacomo Sorelli, Vyacheslav N. Shatokhin, Claudia Reinlein, and Andreas Buchleitner</p><p>Entanglement degradation of orbital-angular-momentum modes can be prevented using adaptive optics. The results prove the possibility of significantly reducing the crosstalk of modes, thereby making entanglement available even under moderate atmospheric turbulence conditions.</p><img src="//d22izw7byeupn1.cloudfront.net/journals/PRA/key_images/10.1103/PhysRevA.97.012321.png" width="200" height=\"100\"><br/><p>[Phys. Rev. A 97, 012321] Published Fri Jan 19, 2018</p>Fri, 19 Jan 2018 11:00:00 +0100PRA: Quantum information: Ultimate entanglement robustness of two-qubit states against general local noises
http://link.aps.org/doi/10.1103/PhysRevA.97.012322
<p>Author(s): Sergey N. Filippov, Vladimir V. Frizen, and Daria V. Kolobova</p><p>We study the problem of optimal preparation of a bipartite entangled state, which remains entangled the longest time under action of local qubit noises. We show that for unital noises, such a state is always maximally entangled, whereas for nonunital noises, it is not. We develop a decomposition tec...</p><br/><p>[Phys. Rev. A 97, 012322] Published Fri Jan 19, 2018</p>Fri, 19 Jan 2018 11:00:00 +0100PRA: Quantum information: Qudit hypergraph states and their properties
http://link.aps.org/doi/10.1103/PhysRevA.97.012323
<p>Author(s): Fei-Lei Xiong, Yi-Zheng Zhen, Wen-Fei Cao, Kai Chen, and Zeng-Bing Chen</p><p>Hypergraph states, a generalization of graph states, constitute a large class of quantum states with intriguing nonlocal properties, and they have promising applications in quantum information science and technology. In this paper, we study some features of an independently proposed generalization o...</p><br/><p>[Phys. Rev. A 97, 012323] Published Fri Jan 19, 2018</p>Fri, 19 Jan 2018 11:00:00 +0100arXiv.org: Quantum Physics: Topological energy conversion through bulk/boundary of driven systems. (arXiv:1801.05811v1 [cond-mat.mes-hall])
http://arxiv.org/abs/1801.05811
<p>Combining physical and synthetic dimensions allows a controllable realization
and manipulation of high dimensional topological states. In our work, we
introduce two quasiperiodically driven 1D systems which enable tunable
topological energy conversion between different driving sources. Using three
drives, we realize a 4D quantum Hall state which allows energy conversion
between two of the drives within the bulk of the 1D system.<p><a href="http://arxiv.org/abs/1801.05811">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100arXiv.org: Quantum Physics: Solving quantum impurity problems in and out of equilibrium with variational approach. (arXiv:1801.05825v1 [cond-mat.str-el])
http://arxiv.org/abs/1801.05825
<p>An efficient variational approach is developed to solve in- and
out-of-equilibrium problems of generic quantum spin-impurity systems. Employing
the discrete symmetry hidden in spin-impurity models, we present a new
canonical transformation that completely decouples the impurity and bath
degrees of freedom.<p><a href="http://arxiv.org/abs/1801.05825">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100arXiv.org: Quantum Physics: Solvable two dimensional time-dependent non-Hermitian quantum systems with infinite dimensional Hilbert space in the broken PT-regime. (arXiv:1801.05828v1 [quant-ph])
http://arxiv.org/abs/1801.05828
<p>We provide exact analytical solutions for a two dimensional explicitly
time-dependent non-Hermitian quantum system. While the time-independent variant
of the model studied is in the broken PT-symmetric phase for the entire range
of the model parameters, and has therefore a partially complex energy
eigenspectrum, its time-dependent version has real energy expectation values at
all times. In our solution procedure we compare the two equivalent approaches
of directly solving the time-dependent Dyson equation with one employing the
Lewis-Riesenfeld method of invariants.<p><a href="http://arxiv.org/abs/1801.05828">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100arXiv.org: Quantum Physics: Lessons on electronic decoherence in molecules from exact modeling. (arXiv:1801.05846v1 [physics.chem-ph])
http://arxiv.org/abs/1801.05846
<p>Electronic decoherence processes in molecules and materials are usually
thought and modeled via schemes for the system-bath evolution in which the bath
is treated either implicitly or approximately. Here we present computations of
the electronic decoherence dynamics of a model many-body molecular system
described by the Su-Schreefer-Heeger Hamiltonian with Hubbard electron-electron
interactions using an exact method in which both electronic and nuclear degrees
of freedom are taken into account explicitly and fully quantum mechanically.<p><a href="http://arxiv.org/abs/1801.05846">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100arXiv.org: Quantum Physics: AC Magnetic Field Sensing Using Continuous-Wave Optically Detected Magnetic Resonance of Nitrogen Vacancy Centers in Diamond. (arXiv:1801.05865v1 [quant-ph])
http://arxiv.org/abs/1801.05865
<p>Nitrogen-vacancy (NV) centers in diamond are considered sensors for detecting
magnetic fields. Pulsed optically detected magnetic resonance (ODMR) is
typically used to detect AC magnetic fields; however, this technique can only
be implemented after careful calibration that involves aligning an external
static magnetic field, measuring continuous-wave (CW) ODMR, determining the
Rabi frequency, and setting the microwave phase. In contrast, CW-ODMR can be
simply implemented by continuous application of green CW laser and a microwave
filed.<p><a href="http://arxiv.org/abs/1801.05865">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100arXiv.org: Quantum Physics: Quantum phase transition in an effective three-mode model of interacting bosons. (arXiv:1801.05866v1 [quant-ph])
http://arxiv.org/abs/1801.05866
<p>In this work we study an effective three-mode model describing interacting
bosons. These bosons can be considered as exciton-polaritons in a semiconductor
microcavity at the magic angle. This model exhibits quantum phase transition
(QPT) when the parameters of the corresponding Hamiltonian are continuously
varied. The properties of the Hamiltonian spectrum (e.g., the distance between
two adjacent energy levels) and the phase space structure of the thermodynamic
limit of the model are used to indicate QPT.<p><a href="http://arxiv.org/abs/1801.05866">read more</a></p>
Fri, 19 Jan 2018 05:45:09 +0100