Records |
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 |
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Thesis |
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Publisher |
Amer Scientific Publishers |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1546-1955 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000322605800007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1528 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
Amer Scientific Publishers |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1546-1955 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000322605800014 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1529 |
Permanent link to this record |
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Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
Interpretation of the depths of maximum of extensive air showers measured by the Pierre Auger Observatory |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
02 |
Issue |
2 |
Pages |
026 - 20pp |
Keywords |
ultra high energy cosmic rays; cosmic ray experiments |
Abstract |
To interpret the mean depth of cosmic ray air shower maximum and its dispersion, we parametrize those two observables as functions of the first two moments of the ln A distribution. We examine the goodness of this simple method through simulations of test mass distributions. The application of the parameterization to Pierre Auger Observatory data allows one to study the energy dependence of the mean ln A and of its variance under the assumption of selected hadronic interaction models. We discuss possible implications of these dependences in term of interaction models and astrophysical cosmic ray sources. |
Address |
[Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.; Santo, C. E.; Sidelnik, I.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000315576400026 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1360 |
Permanent link to this record |
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Author |
Cline, J.M.; Vincent, A.C. |
Title |
Cosmological origin of anomalous radio background |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
02 |
Issue |
2 |
Pages |
011 - 23pp |
Keywords |
cosmology of theories beyond the SM; dark matter theory; extragalactic magnetic fields |
Abstract |
The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate several potential mechanisms and show that injection of relativistic electrons through late decays of a metastable particle can give rise to the observed excess radio spectrum through synchrotron emission. However, constraints from the cosmic microwave background (CMB) anisotropy, on injection of charged particles and on the primordial magnetic field, present a challenge. The simplest scenario is with a greater than or similar to 9 GeV particle decaying into e(+)e(-) at a redshift of z similar to 5, in a magnetic field of similar to 5 μG, which exceeds the CMB B-field constraints, unless the field was generated after decoupling. Decays into exotic millicharged particles can alleviate this tension, if they emit synchroton radiation in conjunction with a sufficiently large background magnetic field of a dark U(1)' gauge field. |
Address |
[Cline, James M.] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada, Email: jcline@physics.mcgill.ca; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000315576400011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1361 |
Permanent link to this record |
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Author |
de Putter, R.; Verde, L.; Jimenez, R. |
Title |
Testing LTB void models without the cosmic microwave background or large scale structure: new constraints from galaxy ages |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
02 |
Issue |
2 |
Pages |
047 - 22pp |
Keywords |
dark energy experiments; dark energy theory; galaxy evolution |
Abstract |
We present new observational constraints on inhomogenous models based on observables independent of the CMB and large-scale structure. Using Bayesian evidence we find very strong evidence for homogeneous LCDM model, thus disfavouring inhomogeneous models. Our new constraints are based on quantities independent of the growth of perturbations and rely on cosmic clocks based on atomic physics and on the local density of matter. |
Address |
[de Putter, Roland; Verde, Licia; Jimenez, Raul] Univ Barcelona IEEC UB, ICC, Barcelona 08028, Spain, Email: rdeputter@icc.ub.edu; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000315576400047 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1362 |
Permanent link to this record |