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

Annalen der Physik

The Effect of the Multi‐Environment for Quantum Correlation: Geometry Discord vs Quantum Discord

Chang‐Chun Ding, Qinsheng Zhu, Shao‐Yi Wu, Wei Lai

Published Jul 20, 2017• 3 citations
Publisher

Abstract

Abstract A two qubits system interacting with two independent spin‐environments connecting with the third environment is constructed in order to demonstrate the effect of the multi‐environment for quantum correlation. In this process, the freezing phenomenon appears for SCI and X states under Quantum Discord and Geometric Discord measures, respectively, but not for the same initial state measured by different measures. Meanwhile, the properties of the freezing platform, characterized by the collapse, revival and persistent time, are researched by the different parameters. The result of this paper may pave a way to control quantum correlation and design nanospintronic devices.

DOI
10.1002/andp.201700014

Related papers

The Controllability of Quantum Correlation Under Geometry and Entropy Discords

Xiaoyu Li, Yiming Huang, Qin-Sheng Zhu +2 more

Quantum correlation plays a critical role in the maintenance of quantum information processing and nanometer device design. In the past two decades, several quantitative methods had been proposed to study the quantum correlation of certain open quantum systems, including the geometry and entropy style discord methods. However, there are differences among these quantification methods, which promote a deep understanding of the quantum correlation. In this paper, a novel time-dependent three environmental open system model is established to study the quantum correlation. This system model interacts with two independent spin-environments (two spin-environments are connected to the other spin-environment) respectively. We have calculated and compared the changing properties of the quantum correlation under three kinds of geometry and two entropy discords, especially for the freezing phenomenon. At the same time, some original and novel changing behaviors of the quantum correlation under different time-dependent parameters are studied, which is helpful to achieve the optimal revival of the quantum discord and the similar serrated form of the freezing phenomenon. Finally, it shows the controllability of the freezing correlation and the robustness of these methods by adjusting time-dependent parameters. This work provides a new way to control the quantum correlation and design nanospintronic devices.

Computers, materials & continua/Computers, materials & continua (Print)•Jan 1, 2021•0 citations

The freezing Rènyi quantum discord

Xiao-Yu Li, Qin-Sheng Zhu, Mingzhe Zhu +3 more

As a universal quantum character of quantum correlation, the freezing phenomenon is researched by geometry and quantum discord methods, respectively. In this paper, the properties of Rènyi discord is studied for two independent Dimer System coupled to two correlated Fermi-spin environments under the non-Markovian condition. We further demonstrate that the freezing behaviors still exist for Rènyi discord and study the effects of different parameters on this behaviors.

arXiv:1804.02791•Scientific Reports•Oct 14, 2019•8 citations

Freezing of geometric discords for two qutrits in environments

Wei Xiao, Mei-Yun Zhen, Xi-Wen Hou

Several measures of geometric discords have been recently proposed and mostly characterized in qubits. In this work, the dynamics of four measures of geometric discords is studied for two kinds of initial states in the two-qutrit model under environments. It is shown that four indicators can display freezing in Markovian regime and multiple freezing with multiple sudden changes in non-Markovian regime for suitable initial states and model parameters. Moreover, those measures evolve in a similar manner, but they differ from the decaying or increasing rate, the oscillatory amplitude and the time interval of freezing. However, they do not exhibit any freezing for the general Bell states. The dynamical hierarchy is discussed for those indicators. Those are helpful to understand the rich phenomena of discordant dynamics in open qutrits.

International Journal of Quantum Information•Jul 10, 2022•3 citations

Experimentally freezing quantum discord in a dephasing environment using dynamical decoupling

Harpreet Singh, Arvind, Kavita Dorai

The discovery of the intriguing phenomenon that certain kinds of quantum correlations remain impervious to noise up to a specific point in time and then suddenly decay, has generated immense recent interest. We exploit dynamical decoupling sequences to prolong the persistence of time-invariant quantum correlations in a system of two NMR qubits decohering in independent dephasing environments. We experimentally prepare two-qubit Bell-diagonal quantum states that interact with individual noise channels and demonstrate that we are able to freeze quantum correlations over long time scales via dynamical decoupling. Our results have important implications for experimental quantum control and for quantum information processing protocols.

arXiv:1610.02755•Europhysics Letters (EPL)•Jun 1, 2017•16 citations

Observation of freezing phenomenon in high-dimensional quantum correlation dynamics

Yue Fu, Wenquan Liu, Yunhan Wang +4 more

Quantum information processing (QIP) based on high-dimensional quantum systems provides unique advantages and new potentials where high-dimensional quantum correlations (QCs) play vital roles. Exploring the resistance of QCs against noises is crucial as QCs are fragile due to complex and unavoidable system-environment interactions. In this study, we investigate the performance of high-dimensional QCs under local dephasing noise using a single nitrogen-vacancy center in diamond. A freezing phenomenon in the high-dimensional quantum discord dynamics was observed, showing discord is robust against local dephasing noise. Utilizing a robustness metric known as freezing index, we found that the discord of qutrits outperforms their qubits counterpart when confronted with dephasing noise. Furthermore, we developed a geometric picture to explain this intriguing freezing phenomenon phenomenon. Our findings highlight the potential of utilizing discord as a physical resource for advancing QIP in high-dimensional quantum settings.

arXiv:2411.01538•Nov 3, 2024•0 citations

Universality of the freezing of geometric quantum correlations

Marco Cianciaruso, Thomas R. Bromley, Wojciech Roga +3 more

Abstract. Quantum correlations in a composite system can be measured by resorting to a geometric approach, according to which the distance from the state of the system to a suitable set of classically correlated states is considered. We show that all distance functions, which respect natural assumptions of invariance under transposition, convexity, and contractivity under quantum channels, give rise to geometric quantifiers of quantum correlations which exhibit the peculiar freezing phenomenon, i.e., remain constant during the evolution of a paradigmatic class of states of two qubits each independently interacting with a non-dissipative decohering environment. Our results demonstrate from first principles that freezing of geometric quantum correlations is independent of the adopted distance and therefore universal. This finding paves the way to a deeper physical interpretation and future practical exploitation

•Aug 17, 2016•1 citation
Abstract A two qubits system interacting with two independent spin‐environments connecting with the third environment is constructed in order to demonstrate the effect of the multi‐environment for quantum correlation. In this process, the freezing phenomenon appears for SCI and X states under Quantum Discord and Geometric Discord measures, respectively, but not for the same initial state measured by different measures. Meanwhile, the properties of the freezing platform, characterized by the collapse, revival and persistent time, are researched by the different parameters. The result of this paper may pave a way to control quantum correlation and design nanospintronic devices.
Quantum correlation plays a critical role in the maintenance of quantum information processing and nanometer device design. In the past two decades, several quantitative methods had been proposed to study the quantum correlation of certain open quantum systems, including the geometry and entropy style discord methods. However, there are differences among these quantification methods, which promote a deep understanding of the quantum correlation. In this paper, a novel time-dependent three environmental open system model is established to study the quantum correlation. This system model interacts with two independent spin-environments (two spin-environments are connected to the other spin-environment) respectively. We have calculated and compared the changing properties of the quantum correlation under three kinds of geometry and two entropy discords, especially for the freezing phenomenon. At the same time, some original and novel changing behaviors of the quantum correlation under different time-dependent parameters are studied, which is helpful to achieve the optimal revival of the quantum discord and the similar serrated form of the freezing phenomenon. Finally, it shows the controllability of the freezing correlation and the robustness of these methods by adjusting time-dependent parameters. This work provides a new way to control the quantum correlation and design nanospintronic devices.
Several measures of geometric discords have been recently proposed and mostly characterized in qubits. In this work, the dynamics of four measures of geometric discords is studied for two kinds of initial states in the two-qutrit model under environments. It is shown that four indicators can display freezing in Markovian regime and multiple freezing with multiple sudden changes in non-Markovian regime for suitable initial states and model parameters. Moreover, those measures evolve in a similar manner, but they differ from the decaying or increasing rate, the oscillatory amplitude and the time interval of freezing. However, they do not exhibit any freezing for the general Bell states. The dynamical hierarchy is discussed for those indicators. Those are helpful to understand the rich phenomena of discordant dynamics in open qutrits.
The discovery of the intriguing phenomenon that certain kinds of quantum correlations remain impervious to noise up to a specific point in time and then suddenly decay, has generated immense recent interest. We exploit dynamical decoupling sequences to prolong the persistence of time-invariant quantum correlations in a system of two NMR qubits decohering in independent dephasing environments. We experimentally prepare two-qubit Bell-diagonal quantum states that interact with individual noise channels and demonstrate that we are able to freeze quantum correlations over long time scales via dynamical decoupling. Our results have important implications for experimental quantum control and for quantum information processing protocols.
Quantum information processing (QIP) based on high-dimensional quantum systems provides unique advantages and new potentials where high-dimensional quantum correlations (QCs) play vital roles. Exploring the resistance of QCs against noises is crucial as QCs are fragile due to complex and unavoidable system-environment interactions. In this study, we investigate the performance of high-dimensional QCs under local dephasing noise using a single nitrogen-vacancy center in diamond. A freezing phenomenon in the high-dimensional quantum discord dynamics was observed, showing discord is robust against local dephasing noise. Utilizing a robustness metric known as freezing index, we found that the discord of qutrits outperforms their qubits counterpart when confronted with dephasing noise. Furthermore, we developed a geometric picture to explain this intriguing freezing phenomenon phenomenon. Our findings highlight the potential of utilizing discord as a physical resource for advancing QIP in high-dimensional quantum settings.
Abstract. Quantum correlations in a composite system can be measured by resorting to a geometric approach, according to which the distance from the state of the system to a suitable set of classically correlated states is considered. We show that all distance functions, which respect natural assumptions of invariance under transposition, convexity, and contractivity under quantum channels, give rise to geometric quantifiers of quantum correlations which exhibit the peculiar freezing phenomenon, i.e., remain constant during the evolution of a paradigmatic class of states of two qubits each independently interacting with a non-dissipative decohering environment. Our results demonstrate from first principles that freezing of geometric quantum correlations is independent of the adopted distance and therefore universal. This finding paves the way to a deeper physical interpretation and future practical exploitation