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Author Arnault, P.; Pepper, B.; Perez, A.
Title Quantum walks in weak electric fields and Bloch oscillations Type Journal Article
Year 2020 Publication Physical Review A Abbreviated Journal Phys. Rev. A
Volume 101 Issue 6 Pages 062324 - 12pp
Keywords
Abstract Bloch oscillations appear when an electric field is superimposed on a quantum particle that evolves on a lattice with a tight-binding Hamiltonian (TBH), i.e., evolves via what we call an electric TBH; this phenomenon will be referred to as TBH Bloch oscillations. A similar phenomenon is known to show up in so-called electric discrete-time quantum walks (DQWs) [C. Cedzich et al., Phys. Rev. Lett. 111, 160601 (2013);] this phenomenon will be referred to as DQW Bloch oscillations. This similarity is particularly salient when the electric field of the DQW is weak. For a wide, i.e., spatially extended, initial condition, one numerically observes semiclassical oscillations, i.e., oscillations of a localized particle, for both the electric TBH and the electric DQW. More precisely, the numerical simulations strongly suggest that the semiclassical DQW Bloch oscillations correspond to two counterpropagating semiclassical TBH Bloch oscillations. In this work it is shown that, under certain assumptions, the solution of the electric DQW for a weak electric field and a wide initial condition is well approximated by the superposition of two continuous-time expressions, which are counterpropagating solutions of an electric TBH whose hopping amplitude is the cosine of the arbitrary coin-operator mixing angle. In contrast, if one wishes the continuous-time approximation to hold for spatially localized initial conditions, one needs at least the DQW to be lazy, as suggested by numerical simulations and by the fact that this has been proven in the case of a vanishing electric field [F. W. Strauch, Phys. Rev. A 74, 030301(R) (2006)].
Address [Arnault, Pablo; Pepper, Benjamin; Perez, A.] Univ Valencia, CSIC, Dept Fis Teor, Cerrer Dr Moliner 50, Burjassot 46100, Spain, Email: pablo.arnault@ific.uv.es;
Corporate Author Thesis
Publisher (up) Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947 ISBN Medium
Area Expedition Conference
Notes WOS:000541400900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4431
Permanent link to this record
 
 
Author Perez, A.; Romanelli, A.
Title Spatially Dependent Decoherence and Anomalous Diffussion of Quantum Walks Type Journal Article
Year 2013 Publication Journal of Computational and Theoretical Nanoscience Abbreviated Journal J. Comput. Theor. Nanosci.
Volume 10 Issue 7 Pages 1591-1595
Keywords Decoherence; Quantum Walk; Non-Translational Invariance
Abstract We analyze the long time behavior of a discrete time quantum walk subject to decoherence with a strong spatial dependence, acting on one half of the lattice. We show that, except for limiting cases on the decoherence parameter, the quantum walk at late times behaves sub-ballistically, meaning that the characteristic features of the quantum walk are not completely spoiled. Contrarily to expectations, the asymptotic behavior is non Markovian, and depends on the amount of decoherence. This feature can be clearly shown on the long time value of the Generalized Chiral Distribution (GCD).
Address [Perez, A.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain
Corporate Author Thesis
Publisher (up) Amer Scientific Publishers Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1546-1955 ISBN Medium
Area Expedition Conference
Notes WOS:000322605800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1528
Permanent link to this record
 
 
Author Hinarejos, M.; Bañuls, M.C.; Perez, A.
Title A Study of Wigner Functions for Discrete-Time Quantum Walks Type Journal Article
Year 2013 Publication Journal of Computational and Theoretical Nanoscience Abbreviated Journal J. Comput. Theor. Nanosci.
Volume 10 Issue 7 Pages 1626-1633
Keywords Quantum Walk; Wigner Function; Negativity
Abstract We perform a systematic study of the discrete time Quantum Walk on one dimension using Wigner functions, which are generalized to include the chirality (or coin) degree of freedom. In particular, we analyze the evolution of the negative volume in phase space, as a function of time, for different initial states. This negativity can be used to quantify the degree of departure of the system from a classical state. We also relate this quantity to the entanglement between the coin and walker subspaces.
Address [Hinarejos, M.; Perez, A.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain
Corporate Author Thesis
Publisher (up) Amer Scientific Publishers Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1546-1955 ISBN Medium
Area Expedition Conference
Notes WOS:000322605800014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1529
Permanent link to this record
 
 
Author Kim, J.S.; Lopez-Fogliani, D.E.; Perez, A.D.; Ruiz de Austri, R.
Title The new (g-2)(mu) and right-handed sneutrino dark matter Type Journal Article
Year 2022 Publication Nuclear Physics B Abbreviated Journal Nucl. Phys. B
Volume 974 Issue Pages 115637 - 23pp
Keywords
Abstract In this paper we investigate the (g – 2)(mu) discrepancy in the context of the R-parity conserving next-to minimal supersymmetric Standard Model plus right-handed neutrinos superfields. The model has the ability to reproduce neutrino physics data and includes the interesting possibility to have the right-handed sneutrino as the lightest supersymmetric particle and a viable dark matter candidate. Since right-handed sneutrinos are singlets, no new contributions for delta a(mu) with respect to the MSSM and NMSSM are present. However, the possibility to have the right-handed sneutrino as the lightest supersymmetric particle opens new ways to escape Large Hadron Collider and direct detection constraints. In particular, we find that dark matter masses within 10 less than or similar to m((upsilon) over tildeR) less than or similar to 600 GeV are fully compatible with current experimental constraints. Remarkably, not only spectra with light sleptons are needed, but we obtain solutions with m((mu) over tilde) greater than or similar to 600 GeV in the entire dark matter mass range that could be probed by new (g – 2)(mu) data in the near future. In addition, dark matter direct detection experiments will be able to explore a sizable portion of the allowed parameter space with mvR < 300 GeV, while indirect detection experiments will be able to probe a much smaller fraction within 200 less than or similar to m((nu)over tilde>R) less than or similar to 350 GeV.
Address [Kim, Jong Soo] Univ Witwatersrand, Sch Phys, Johannesburg, South Africa, Email: jongsoo.kim@tu-dortmund.de;
Corporate Author Thesis
Publisher (up) Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0550-3213 ISBN Medium
Area Expedition Conference
Notes WOS:000760320700019 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5135
Permanent link to this record
 
 
Author de Vega, I.; Bañuls, M.C.; Perez, A.
Title Effects of dissipation on an adiabatic quantum search algorithm Type Journal Article
Year 2010 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 12 Issue Pages 123010 - 19pp
Keywords
Abstract According to recent studies (Amin et al 2008 Phys. Rev. Lett. 100 060503), the effect of a thermal bath may improve the performance of a quantum adiabatic search algorithm. In this paper, we compare the effects of such a thermal environment on the algorithm performance with those of a structured environment similar to the one encountered in systems coupled to an electromagnetic field that exists within a photonic crystal. Whereas for all the parameter regimes explored here, the algorithm performance is worsened by contact with a thermal environment, the picture appears to be different when one considers a structured environment. In this case we show that by tuning the environment parameters to certain regimes, the algorithm performance can actually be improved with respect to the closed system case. Additionally, the relevance of considering the dissipation rates as complex quantities is discussed in both cases. More specifically, we find that the imaginary part of the rates cannot be neglected with the usual argument that it simply amounts to an energy shift and in fact influences crucially the system dynamics.
Address [de Vega, Ines] Univ Ulm, Inst Theoret Phys, D-89069 Ulm, Germany, Email: ines.devega@uni-ulm.de
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes ISI:000285582800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 303
Permanent link to this record
 
 
Author Hinarejos, M.; Perez, A.; Bañuls, M.C.
Title Wigner function for a particle in an infinite lattice Type Journal Article
Year 2012 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 14 Issue Pages 103009 - 19pp
Keywords
Abstract We study the Wigner function for a quantum system with a discrete, infinite-dimensional Hilbert space, such as a spinless particle moving on a one-dimensional infinite lattice. We discuss the peculiarities of this scenario and of the associated phase-space construction, propose a meaningful definition of the Wigner function in this case and characterize the set of pure states for which it is non-negative. We propose a measure of non-classicality for states in this system, which is consistent with the continuum limit. The prescriptions introduced here are illustrated by applying them to localized and Gaussian states and to their superpositions.
Address [Banuls, M. C.] Max Planck Inst Quantum Opt, D-85748 Garching, Germany, Email: mari.banuls@mpq.mpg.de
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000309396700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1180
Permanent link to this record
 
 
Author Hinarejos, M.; Perez, A.; Roldan, E.; Romanelli, A.; de Valcarcel, G.J.
Title Understanding and controlling N-dimensional quantum walks via dispersion relations: application to the two-dimensional and three-dimensional Grover walks-diabolical points and more Type Journal Article
Year 2013 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 15 Issue Pages 073041 - 31pp
Keywords
Abstract The discrete quantum walk in N dimensions is analyzed from the perspective of its dispersion relations. This allows understanding known properties, as well as designing new ones when spatially extended initial conditions are considered. This is done by deriving wave equations in the continuum, which are generically of the Schrodinger type, and allows devising interesting behavior, such as ballistic propagation without deformation, or the generation of almost flat probability distributions, which is corroborated numerically. There are however special points where the energy surfaces display intersections and, near them, the dynamics is entirely different. Applications to the two- and three-dimensional Grover walks are presented.
Address [Hinarejos, Margarida; Perez, Armando] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: Armando.Perez@uv.es
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000322110600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1504
Permanent link to this record
 
 
Author Hinarejos, M.; Bañuls, M.C.; Perez, A.
Title Wigner formalism for a particle on an infinite lattice: dynamics and spin Type Journal Article
Year 2015 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 17 Issue Pages 013037 - 16pp
Keywords Wigner functions; dynamics on a lattice; spin-dependent forces
Abstract The recently proposed Wigner function for a particle in an infinite lattice (Hinarejos M, Banuls MC and Perez A 2012 New J. Phys. 14 103009) is extended here to include an internal degree of freedom as spin. This extension is made by introducing a Wigner matrix. The formalism is developed to account for dynamical processes, with or without decoherence. We show explicit solutions for the case of Hamiltonian evolution under a position-dependent potential, and for evolution governed by a master equation under some simple models of decoherence, for which the Wigner matrix formalism is well suited. Discrete processes are also discussed. Finally, we discuss the possibility of introducing a negativity concept for the Wigner function in the case where the spin degree of freedom is included.
Address [Hinarejos, M.; Perez, A.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: banulsm@mpq.mpg.de
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000348759800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2101
Permanent link to this record
 
 
Author Di Molfetta, G.; Perez, A.
Title Quantum walks as simulators of neutrino oscillations in a vacuum and matter Type Journal Article
Year 2016 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 18 Issue Pages 103038 - 8pp
Keywords quantum walks; neutrino oscillations; quantum simulation
Abstract We analyze the simulation of Dirac neutrino oscillations using quantum walks, both in a vacuum and in matter. We show that this simulation, in the continuum limit, reproduces a set of coupled Dirac equations that describe neutrino flavor oscillations, and we make use of this to establish a connection with neutrino phenomenology, thus allowing one to fix the parameters of the simulation for a given neutrino experiment. We also analyze how matter effects for neutrino propagation can be simulated in the quantum walk. In this way, important features, such as the MSW effect, can be incorporated. Thus, the simulation of neutrino oscillations with the help of quantum walks might be useful to illustrate these effects in extreme conditions, such as the solar interior or supernovae.
Address [Di Molfetta, G.] Univ Valencia, CSIC, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Spain, Email: giuseppe.dimolfetta@lif.univ-mrs.fr
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000386816100004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2846
Permanent link to this record
 
 
Author Hinarejos, M.; Bañuls, M.C.; Perez, A.; de Vega, I.
Title Non-Markovianity and memory of the initial state Type Journal Article
Year 2017 Publication Journal of Physics A Abbreviated Journal J. Phys. A
Volume 50 Issue 32 Pages 335301 - 17pp
Keywords non-Markovianity; quantum distinguisability; quantum fidelity
Abstract We explore in a rigorous manner the intuitive connection between the non-Markovianity of the evolution of an open quantum system and the performance of the system as a quantum memory. Using the paradigmatic case of a two-level open quantum system coupled to a bosonic bath, we compute the recovery fidelity, which measures the best possible performance of the system to store a qubit of information. We deduce that this quantity is connected, but not uniquely determined, by the non-Markovianity, for which we adopt the Breuer-Laine-Piilo measure proposed in Breuer et al (2009 Phys. Rev. Lett. 103 210401). We illustrate our findings with explicit calculations for the case of a structured environment.
Address [Hinarejos, Margarida] Univ Republica, Fac Ingn, Inst Fis, Av Julio Herrera y Reissig 565, Montevideo 11300, Uruguay, Email: Armando.Perez@uv.es
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-8113 ISBN Medium
Area Expedition Conference
Notes WOS:000405672800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3206
Permanent link to this record