Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1804.05171 · Annalen der Physik

Quantum Temporal Steering in a Dephasing Channel With Quantum Criticality

Бо Лю, Yixiao Huang, Zhe Sun

Published Mar 7, 2018• 8 citations
arXivHTMLPDF

Abstract

Abstract We investigate the quantum temporal steering (TS), i.e., a temporal analogue of Einstein‐Podolsky‐Rosen steering, in a dephasing channel which is modeled by a central spin half surrounded by a spin‐1/2 XY chain where quantum phase transition happens. The TS parameter and the TS weight are employed to characterize the TS dynamics. We analytically obtain the dependence of on the decoherence factor. The numerical results show an obvious suppression of and when the XY chain approaches to the critical point. In view of the significance of quantum channel, we develop a new concept, TS weight power, in order to quantify the capacity of the quantum channel in dominating TS behavior. This new quantity enables us to indicate the quantum criticality of the environment by the quantum correlation of TS in the coupled system.

DOI
10.1002/andp.201700373

Related papers

Einstein-Podolsky-Rosen Steering in Quantum Phase Transition

Chunfeng Wu, Jing‐Ling Chen, Dong-Ling Deng +3 more

We investigate the Einstein-Podolsky-Rosen (EPR) steering and its criticality in quantum phase transition. It is found that the EPR steerability function of the ground state of XY spin chain exhibits nonanalytic feature in the vicinity of a quantum phase transition by showing that its derivative with respect to anisotropy parameter diverges at the critical point. We then verify the universality of the critical phenomena of the EPR steerability function in the system. We also use two-qubit EPR-steering inequality to explore the relation between EPR steering and quantum phase transition.

arXiv:1201.0243•Dec 31, 2011•0 citations

Einstein–Podolsky–Rosen steering in critical systems

W. W. Cheng, K Wang, W F Wang +1 more

Abstract We explore Einstein–Podolsky–Rosen steering, measured by steering robustness, in the ground states of several typical models that exhibit a quantum phase transition. For the anisotropic XY model, steering robustness approaches zero around the critical point and vanishes in the ferromagnetic phase despite the fact that there exist other quantum nonlocalities, e.g. quantum entanglement. For the Heisenberg XXZ model, steering robustness exhibits some similar behavior as entanglement around the infinite-order quantum phase transition point Δ = 1, e.g. reaching its maximum. As a further example, we also consider steering robustness in the Lipkin–Meshkov–Glick collective spin model. It is then shown that steering robustness disappears at the transition point and remains at zero in the fully polarized symmetric phase, just like the behavior of entanglement and Bell nonlocality.

Journal of Physics B Atomic Molecular and Optical Physics•Jan 28, 2019•5 citations

Scaling of Einstein–Podolsky–Rosen steering in spin chains

W. W. Cheng, Jyrki Piilo

Abstract Symmetric quantum properties and correlations have been often used earlier to study quantum phase transitions in many body systems and spin models. However, the use of asymmetric quantum features, such as steering, have attracted smaller amount of attention in this context, so far. We study EPR steering and quantum phase transitions in the Ising model in transverse field and in the anisotropic XY model by using steering robustness and quantum renormalization group method. The key ingredients of the quantum criticality near the critical points, such as finite-size scaling behaviour and critical exponents, are investigated in detail with two commonly used spin models. Our results show that the first derivative of steering robustness between two blocks diverges near the quantum phase transition points for both models, and exhibits a finite-size scaling effect. Moreover, we explore in detail the asymmetric character of EPR steering, by taking into accounts finite-size effects and measurement number, in the reduced block state in the anisotropic XY model. The results imply that one-way EPR steering does not exist in large system under the limit L → ∞ despite the fact that EPR steering for the reduced block state is asymmetric.

Physica Scripta•Oct 22, 2019•5 citations

Experimental temporal quantum steering

Karol Bartkiewicz, Antonín Černoch, Karel Lemr +2 more

Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering.

arXiv:1602.09133•Scientific Reports•Nov 30, 2016•43 citations

Spin squeezing under decoherence: Role of the quantum phase transition

Zhe Sun

In order to witness multipartite correlations beyond pairwise entanglement, we study the spin-squeezing evolution of a spin-1/2 ensemble in environments with quantum phase transitions. Each spin half of the ensemble evolves under its own decoherence channel, which is modeled by a central spin 1/2 surrounded by a spin-1/2 $XY$ chain. We employ four spin-squeezing parameters to describe squeezing, and their expressions at time $t$ are analytically calculated for the spin ensemble in a collective initial state. It is found that spin squeezing of an auxiliary ensemble signals very well the critical regions of the environment. Quantum fluctuations of the environment accelerate the decay of spin squeezing and dramatically change spin squeezing.

Physical Review A•Nov 7, 2011•15 citations

Quantifying Non-Markovianity with Temporal Steering

Shin-Liang Chen, Neill Lambert, Che‐Ming Li +3 more

Einstein-Podolsky-Rosen (EPR) steering is a type of quantum correlation which allows one to remotely prepare, or steer, the state of a distant quantum system. While EPR steering can be thought of as a purely spatial correlation, there does exist a temporal analogue, in the form of single-system temporal steering. However, a precise quantification of such temporal steering has been lacking. Here, we show that it can be measured, via semidefinite programing, with a temporal steerable weight, in direct analogy to the recently proposed EPR steerable weight. We find a useful property of the temporal steerable weight in that it is a nonincreasing function under completely positive trace-preserving maps and can be used to define a sufficient and practical measure of strong non-Markovianity.

arXiv:1503.00836•Physical Review Letters•Jan 15, 2016•109 citations
Abstract We investigate the quantum temporal steering (TS), i.e., a temporal analogue of Einstein‐Podolsky‐Rosen steering, in a dephasing channel which is modeled by a central spin half surrounded by a spin‐1/2 XY chain where quantum phase transition happens. The TS parameter and the TS weight are employed to characterize the TS dynamics. We analytically obtain the dependence of on the decoherence factor. The numerical results show an obvious suppression of and when the XY chain approaches to the critical point. In view of the significance of quantum channel, we develop a new concept, TS weight power, in order to quantify the capacity of the quantum channel in dominating TS behavior. This new quantity enables us to indicate the quantum criticality of the environment by the quantum correlation of TS in the coupled system.
We investigate the Einstein-Podolsky-Rosen (EPR) steering and its criticality in quantum phase transition. It is found that the EPR steerability function of the ground state of XY spin chain exhibits nonanalytic feature in the vicinity of a quantum phase transition by showing that its derivative with respect to anisotropy parameter diverges at the critical point. We then verify the universality of the critical phenomena of the EPR steerability function in the system. We also use two-qubit EPR-steering inequality to explore the relation between EPR steering and quantum phase transition.
Abstract We explore Einstein–Podolsky–Rosen steering, measured by steering robustness, in the ground states of several typical models that exhibit a quantum phase transition. For the anisotropic XY model, steering robustness approaches zero around the critical point and vanishes in the ferromagnetic phase despite the fact that there exist other quantum nonlocalities, e.g. quantum entanglement. For the Heisenberg XXZ model, steering robustness exhibits some similar behavior as entanglement around the infinite-order quantum phase transition point Δ = 1, e.g. reaching its maximum. As a further example, we also consider steering robustness in the Lipkin–Meshkov–Glick collective spin model. It is then shown that steering robustness disappears at the transition point and remains at zero in the fully polarized symmetric phase, just like the behavior of entanglement and Bell nonlocality.
Abstract Symmetric quantum properties and correlations have been often used earlier to study quantum phase transitions in many body systems and spin models. However, the use of asymmetric quantum features, such as steering, have attracted smaller amount of attention in this context, so far. We study EPR steering and quantum phase transitions in the Ising model in transverse field and in the anisotropic XY model by using steering robustness and quantum renormalization group method. The key ingredients of the quantum criticality near the critical points, such as finite-size scaling behaviour and critical exponents, are investigated in detail with two commonly used spin models. Our results show that the first derivative of steering robustness between two blocks diverges near the quantum phase transition points for both models, and exhibits a finite-size scaling effect. Moreover, we explore in detail the asymmetric character of EPR steering, by taking into accounts finite-size effects and measurement number, in the reduced block state in the anisotropic XY model. The results imply that one-way EPR steering does not exist in large system under the limit L → ∞ despite the fact that EPR steering for the reduced block state is asymmetric.
Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering.
In order to witness multipartite correlations beyond pairwise entanglement, we study the spin-squeezing evolution of a spin-1/2 ensemble in environments with quantum phase transitions. Each spin half of the ensemble evolves under its own decoherence channel, which is modeled by a central spin 1/2 surrounded by a spin-1/2 XYXYXY chain. We employ four spin-squeezing parameters to describe squeezing, and their expressions at time ttt are analytically calculated for the spin ensemble in a collective initial state. It is found that spin squeezing of an auxiliary ensemble signals very well the critical regions of the environment. Quantum fluctuations of the environment accelerate the decay of spin squeezing and dramatically change spin squeezing.
Einstein-Podolsky-Rosen (EPR) steering is a type of quantum correlation which allows one to remotely prepare, or steer, the state of a distant quantum system. While EPR steering can be thought of as a purely spatial correlation, there does exist a temporal analogue, in the form of single-system temporal steering. However, a precise quantification of such temporal steering has been lacking. Here, we show that it can be measured, via semidefinite programing, with a temporal steerable weight, in direct analogy to the recently proposed EPR steerable weight. We find a useful property of the temporal steerable weight in that it is a nonincreasing function under completely positive trace-preserving maps and can be used to define a sufficient and practical measure of strong non-Markovianity.