Records |
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 |
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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 |
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Thesis |
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Publisher |
Amer Physical Soc |
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 |
1050-2947 |
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:000541400900002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4431 |
Permanent link to this record |
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Author |
Guo, J.J.; Sun, F.X.; Zhu, D.Q.; Gessner, M.; He, Q.Y.; Fadel, M. |
Title |
Detecting Einstein-Podolsky-Rosen steering in non-Gaussian spin states from conditional spin-squeezing parameters |
Type |
Journal Article |
Year |
2023 |
Publication |
Physical Review A |
Abbreviated Journal |
Phys. Rev. A |
Volume |
108 |
Issue |
1 |
Pages |
012435 - 7pp |
Keywords |
|
Abstract |
We present an experimentally practical method to reveal Einstein-Podolsky-Rosen (EPR) steering in non-Gaussian spin states by exploiting a connection to quantum metrology. Our criterion is based on the quantum Fisher information, and uses bounds derived from generalized spin-squeezing parameters that involve measurements of higher-order moments. This leads us to introduce the concept of conditional spin-squeezing parameters, which quantify the metrological advantage provided by conditional states, as well as detect the presence of an EPR paradox. |
Address |
[Guo, Jiajie; Sun, Feng-Xiao; Zhu, Daoquan; He, Qiongyi] Peking Univ, State Key Lab Mesoscop Phys, Sch Phys, Frontiers Sci Ctr Nanooptoelect, Beijing 100871, Peoples R China, Email: manuel.gessner@uv.es; |
Corporate Author |
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Thesis |
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
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 |
2469-9926 |
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:001130449100004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5905 |
Permanent link to this record |