Open Systems & Information Dynamics最新文献

英文中文

Unidirectional Information Flow and Positive Divisibility are Nonequivalent Notions of Quantum Markovianity for Noninvertible Dynamics 单向信息流和正可整除性是不可逆动力学中量子马尔可夫性的非等价概念

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-09-01 DOI: 10.1142/S1230161222500123

Á. Rivas

We construct a dynamical map which is not positive divisible and does not present information backflow either (as measured by trace norm quantifiers). It is formulated for a qutrit system undergoing noninvertible dynamics. This provides an evidence that the two definitions of quantum Markovianity based on the absence of information backflow and positive divisibility are nonequivalent for general noninvertible dynamical maps.

我们构造了一个非正可整除且不存在信息回流的动态映射(由迹范数量词测量)。它是针对一个处于不可逆动力学状态的量子系统而制定的。这证明了基于无信息回流和正可整除的量子马尔可夫性的两个定义对于一般的不可逆动态映射是不等价的。

引用次数: 0

Non-Perturbative Treatment of Open-System Multi-Time Expectation Values in Gaussian Bosonic Environments 高斯玻色子环境下开放系统多时间期望值的非微扰处理

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-09-01 DOI: 10.1142/S1230161222500196

A. Smirne, D. Tamascelli, James Lim, M. Plenio, S. Huelga

We determine the conditions for the equivalence between the multi-time expectation values of a general finite-dimensional open quantum system when interacting with, respectively, an environment undergoing a free unitary evolution or a discrete environment under a free evolution fixed by a proper Gorini-Kossakowski-Lindblad-Sudarshan generator. We prove that the equivalence holds if both environments are bosonic and Gaussian and if the one- and two-time correlation functions of the corresponding interaction operators are the same at all times. This result leads to a non-perturbative evaluation of the multi-time expectation values of operators and maps of open quantum systems interacting with a continuous set of bosonic modes by means of a limited number of damped modes, thus setting the ground for the investigation of open-system multi-time quantities in fully general regimes.

我们确定了一般有限维开放量子系统在分别与经历自由统一演化的环境或由适当的gorini - kossakowski - lindbladd - sudarshan发生器固定的自由演化的离散环境相互作用时，其多时间期望值的等价条件。我们证明了如果两个环境都是玻色子和高斯环境，并且相应的相互作用算子的一时间和两时间相关函数在任何时候都是相同的，则等效性成立。这一结果导致开放量子系统通过有限数量的阻尼模式与连续玻色子模式相互作用的算子和映射的多时间期望值的非摄动评估，从而为研究完全一般状态下的开放系统多时间量奠定了基础。

引用次数: 2

Open Quantum Random Walks and Quantum Markov chains on Trees I: Phase transitions 树上的开放量子随机漫步和量子马尔可夫链I:相变

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-08-31 DOI: 10.1142/s1230161222500032

Farrukh Mukhamedov, Abdessatar Souissi, Tarek Hamdi

In the present paper, we construct QMC (Quantum Markov Chains) associated with Open Quantum Random Walks such that the transition operator of the chain is defined by OQRW and the restriction of QMC to the commutative subalgebra coincides with the distribution $ℙ_{ρ}$ of OQRW. However, we are going to look at the probability distribution as a Markov field over the Cayley tree. Such kind of consideration allows us to investigate phase transition phenomena associated for OQRW within QMC scheme. Furthermore, we first propose a new construction of QMC on trees, which is an extension of QMC considered in [10]. Using such a construction, we are able to construct QMCs on tress associated with OQRW. Our investigation leads to the detection of the phase transition phenomena within the proposed scheme. This kind of phenomena appears for the first time in this direction. Moreover, mean entropies of QMCs are calculated.

本文构造了与开放量子随机漫步相关的QMC(量子马尔可夫链)，使得链的转移算子由OQRW定义，并且QMC对交换子代数的限制与OQRW的分布ρ重合。然而，我们将把概率分布看作是Cayley树上的马尔可夫域。这种考虑使我们能够在QMC方案中研究与OQRW相关的相变现象。此外，我们首先提出了一种新的树上QMC结构，这是[10]中考虑的QMC的扩展。使用这种结构，我们能够在与OQRW相关的树上构建qmc。我们的研究导致在提出的方案中发现相变现象。这种现象在这个方向上还是第一次出现。此外，还计算了qmc的平均熵。

引用次数: 0

Correlations in Noisy Measurements 噪声测量中的相关性

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/s1230161222500093

Seungchan Seo, J. Seong, J. Bae

Although a measurement on the computational basis is devised in quantum computing, e.g., cloud-based quantum computing services, a quantum measurement in a realistic scenario is noisy. In particular, a measurement readout error in the era of noisy-intermediate-scale-quantum technologies is significant. In this work, we consider measurements on multiple qubits in a realistic scenario and present a method of analyzing noise in the measurement. Correlations existing in a noisy measurement are of particular interest so that local and crosstalk errors are introduced: the existence of correlations in a measurement in cloud-based quantum computing services is verified. We then present quantification of local and crosstalk errors and apply it to a noisy measurement in a cloud-based quantum computing service. Our results that analyze measurement errors can be used to mitigate these errors.

尽管在量子计算中设计了基于计算的测量，例如基于云的量子计算服务，但现实场景中的量子测量是有噪声的。特别是，在噪声-中尺度量子技术时代，测量读出误差是显着的。在这项工作中，我们考虑在现实场景中对多个量子位进行测量，并提出了一种分析测量中噪声的方法。存在于噪声测量中的相关性是特别有趣的，因此引入了局部和串扰误差:验证了基于云的量子计算服务中测量中相关性的存在。然后，我们提出了局部和串扰误差的量化，并将其应用于基于云的量子计算服务中的噪声测量。我们分析测量误差的结果可以用来减轻这些误差。

引用次数: 0

Stochastic versus Periodic Quantum Collision Models 随机与周期性量子碰撞模型

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/S1230161222500068

F. Ciccarello

Most literature on quantum collision models (CMs) usually considers periodic weak collisions featuring a fixed waiting time between two next collisions. Some works have yet addressed CMs with random waiting time and strong collisions (stochastic CMs). This short paper discusses how the open dynamics arising from these two types of models can be formally mapped with one another. This can be achieved for a given stochastic CM by constructing an associated periodic CM such that the waiting time randomness of the former is turned into the mixedness of the ancilla’s initial state of the latter, introducing at the same time an additional state of the ancilla. Through this mapping, non-Markovian behaviour arising from a constrained number of stochatic collisions can be linked to initial ancilla–ancilla correlations of the associated periodic CM.

大多数关于量子碰撞模型(CMs)的文献通常考虑具有固定等待时间的周期性弱碰撞。一些研究已经解决了随机等待时间和强碰撞(随机CMs)的CMs。这篇短文讨论了由这两种模型产生的开放动力学是如何相互形式化映射的。对于一个给定的随机CM，这可以通过构造一个相关的周期CM来实现，这样前者的等待时间随机性转化为后者的辅助初始状态的混合性，同时引入辅助的附加状态。通过这种映射，由有限数量的随机碰撞产生的非马尔可夫行为可以与相关周期性CM的初始辅助-辅助相关性联系起来。

引用次数: 1

On the Use of Total State Decompositions for the Study of Reduced Dynamics 全态分解在约化动力学研究中的应用

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/S1230161222500081

A. Smirne, Nina Megier, B. Vacchini

The description of the dynamics of an open quantum system in the presence of initial correlations with the environment needs different mathematical tools than the standard approach to reduced dynamics, which is based on the use of a time-dependent completely positive trace preserving (CPTP) map. Here, we take into account an approach that is based on a decomposition of any possibly correlated bipartite state as a conical combination involving statistical operators on the environment and general linear operators on the system, which allows one to fix the reduced-system evolution via a finite set of time-dependent CPTP maps. In particular, we show that such a decomposition always exists, also for infinite dimensional Hilbert spaces, and that the number of resulting CPTP maps is bounded by the Schmidt rank of the initial global state. We further investigate the case where the CPTP maps are semigroups with generators in the Gorini-Kossakowski-Lindblad-Sudarshan form; for two simple qubit models, we identify the positivity domain defined by the initial states that are mapped into proper states at any time of the evolution fixed by the CPTP semigroups.

在与环境存在初始相关性的情况下，开放量子系统的动力学描述需要不同于简化动力学的标准方法的数学工具，这是基于使用时间相关的完全正迹保持(CPTP)映射。在这里，我们考虑了一种方法，该方法基于将任何可能相关的二部状态分解为涉及环境上的统计算子和系统上的一般线性算子的圆锥组合，它允许人们通过一组有限的时间相关的CPTP映射来固定减少的系统进化。特别地，我们证明了这样的分解总是存在的，对于无限维Hilbert空间也是如此，并且所得到的CPTP映射的数量由初始全局状态的Schmidt秩限定。我们进一步研究了具有Gorini-Kossakowski-Lindblad-Sudarshan形式的半群的CPTP映射;对于两个简单的量子比特模型，我们确定了由初始状态定义的正态域，这些初始状态在CPTP半群固定的进化的任何时间被映射到适当状态。

{"title":"On the Use of Total State Decompositions for the Study of Reduced Dynamics","authors":"A. Smirne, Nina Megier, B. Vacchini","doi":"10.1142/S1230161222500081","DOIUrl":"https://doi.org/10.1142/S1230161222500081","url":null,"abstract":"The description of the dynamics of an open quantum system in the presence of initial correlations with the environment needs different mathematical tools than the standard approach to reduced dynamics, which is based on the use of a time-dependent completely positive trace preserving (CPTP) map. Here, we take into account an approach that is based on a decomposition of any possibly correlated bipartite state as a conical combination involving statistical operators on the environment and general linear operators on the system, which allows one to fix the reduced-system evolution via a finite set of time-dependent CPTP maps. In particular, we show that such a decomposition always exists, also for infinite dimensional Hilbert spaces, and that the number of resulting CPTP maps is bounded by the Schmidt rank of the initial global state. We further investigate the case where the CPTP maps are semigroups with generators in the Gorini-Kossakowski-Lindblad-Sudarshan form; for two simple qubit models, we identify the positivity domain defined by the initial states that are mapped into proper states at any time of the evolution fixed by the CPTP semigroups.","PeriodicalId":54681,"journal":{"name":"Open Systems & Information Dynamics","volume":"34 1","pages":"2250008:1-2250008:20"},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77784525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Kossakowski Matrix and Strict Positivity of Markovian Quantum Dynamics Kossakowski矩阵与马尔可夫量子动力学的严格正性

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/s1230161222500056

J. Agredo, F. Fagnola, D. Poletti

We investigate the relationship between strict positivity of the Kossakowski matrix, irreducibility and positivity improvement properties of Markovian quantum dynamics. We show that for a Gaussian quantum dynamical semigroup strict positivity of the Kossakowski matrix implies irreducibility and, with an additional technical assumption, that the support of any initial state is the whole space for any positive time.

研究了Kossakowski矩阵的严格正性、马尔可夫量子动力学的不可约性和正性改进性质之间的关系。我们证明了高斯量子动力半群的Kossakowski矩阵的严格正性意味着不可约性，并且在一个附加的技术假设下，任何初始状态的支持是任何正时间的整个空间。

引用次数: 0

Nature and Origin of Operators Entering the Master Equation of an Open Quantum System 进入开放量子系统主方程的算子的性质和起源

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/S123016122250010X

Giovanni Spaventa, P. Verrucchi

By exploiting the peculiarities of a recently introduced formalism for describing open quantum systems (the parametric representation with environmental coherent states) we derive an equation of motion for the reduced density operator of an open quantum system that has the same structure of the celebrated Gorini–Kossakowski–Sudarshan–Lindblad equation, but holds regardless of Markovianity being assumed. The operators in our result have explicit expressions in terms of the Hamiltonian describing the interactions with the environment, and can be computed once a specific model is considered. We find that, instead of a single set of Lindblad operators, in the general (non-Markovian) case there one set of Lindblad-like operators for each and every point of a symplectic manifold associated to the environment. This intricacy disappears under some assumptions (which are related to Markovianity and the classical limit of the environment), under which it is possible to recover the usual master-equation formalism. Finally, we find such Lindblad-like operators for two different models of a qubit in a bosonic environment, and show that in the classical limit of the environment their renown master equations are recovered.

通过利用最近引入的用于描述开放量子系统的形式主义的特性(具有环境相干态的参数表示)，我们推导出一个开放量子系统的约化密度算子的运动方程，该方程具有与著名的gorini - kossakowski - sudarshanlindblad方程相同的结构，但无论假设是否为马尔可夫性都成立。在我们的结果中的算子有明确的表达式，描述与环境的相互作用的哈密顿量，并可以计算一旦一个特定的模型被考虑。我们发现，在一般(非马尔可夫)情况下，与环境相关的辛流形的每个点都有一组类林德布莱德算子，而不是一组单一的林德布莱德算子。这种复杂性在一些假设下消失了(这些假设与马尔可夫性和环境的经典极限有关)，在这些假设下，有可能恢复通常的主方程形式主义。最后，我们在玻色子环境中为两个不同的量子比特模型找到了这样的类林德布莱德算子，并证明了在环境的经典极限下，它们著名的主方程是恢复的。

{"title":"Nature and Origin of Operators Entering the Master Equation of an Open Quantum System","authors":"Giovanni Spaventa, P. Verrucchi","doi":"10.1142/S123016122250010X","DOIUrl":"https://doi.org/10.1142/S123016122250010X","url":null,"abstract":"By exploiting the peculiarities of a recently introduced formalism for describing open quantum systems (the parametric representation with environmental coherent states) we derive an equation of motion for the reduced density operator of an open quantum system that has the same structure of the celebrated Gorini–Kossakowski–Sudarshan–Lindblad equation, but holds regardless of Markovianity being assumed. The operators in our result have explicit expressions in terms of the Hamiltonian describing the interactions with the environment, and can be computed once a specific model is considered. We find that, instead of a single set of Lindblad operators, in the general (non-Markovian) case there one set of Lindblad-like operators for each and every point of a symplectic manifold associated to the environment. This intricacy disappears under some assumptions (which are related to Markovianity and the classical limit of the environment), under which it is possible to recover the usual master-equation formalism. Finally, we find such Lindblad-like operators for two different models of a qubit in a bosonic environment, and show that in the classical limit of the environment their renown master equations are recovered.","PeriodicalId":54681,"journal":{"name":"Open Systems & Information Dynamics","volume":"110 1","pages":"2250010:1-2250010:18"},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80551362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Quantifying non-Markovian Memory in a Superconducting Quantum Computer 超导量子计算机中非马尔可夫记忆的量化

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-06-01 DOI: 10.1142/s123016122250007x

Joshua Morris, F. A. Pollock, K. Modi

We analyze the temporal correlations in a sequence of gates by characterizing the performance of a gate conditioned on the gate that preceded it. With this method, we estimate (i) the size of fluctuations in the performance of a gate, i.e., errors due to non-Markovianity; (ii) the length of the memory; and (iii) the total size of the memory. Our results strongly indicate the presence of nontrivial non-Markovian effects in almost all gates in the universal set. However, based on our findings, we discuss the potential for cleaner computation by adequately accounting the non-Markovian nature of the machine.

我们通过描述在其前面的门的条件下的门的性能来分析一系列门的时间相关性。使用这种方法，我们估计(i)门性能波动的大小，即由于非马尔可夫性引起的误差;(ii)记忆的长度;(iii)内存的总大小。我们的结果强烈地表明，在全称集中的几乎所有门上都存在非平凡的非马尔可夫效应。然而，基于我们的发现，我们讨论了通过充分考虑机器的非马尔可夫性质来实现更清洁计算的潜力。

引用次数: 23

Local Generation of Entanglement with Redfield Dynamics Redfield动力学中纠缠的局部生成

IF 0.8 4区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Open Systems & Information Dynamics

Pub Date : 2022-03-01 DOI: 10.1142/S1230161222500019

F. Benatti, D. Chru'sci'nski, R. Floreanini

In phenomenological applications, time evolutions of Bloch-Redfield type are widely adopted for modelling open system dynamics, despite their nonpositive preserving character: this physical inconsistency, that in general shows up at small times, is usually cured by suitably restricting the space of allowed initial states. Nevertheless, additional problems may arise in relation to entanglement: specifically, we show that Redfield dynamics, though being a semigroup, can generate entanglement through a purely local action; moreover, this unphysical effect can persist on long time-scales.

在现象学应用中，布洛赫-雷德菲尔德类型的时间演化被广泛用于建模开放系统动力学，尽管它们具有非正保持特性:这种通常在小时间出现的物理不一致性通常通过适当地限制允许的初始状态的空间来治愈。然而，与纠缠有关的其他问题可能会出现:具体而言，我们表明Redfield动力学虽然是半群，但可以通过纯粹的局部作用产生纠缠;此外，这种非物理效应可以持续很长时间。

引用次数: 4

首页上一页

下一页尾页

类型

全部化学•材料生命科学医学物理工程技术环境•农林材料科学地球科学法学管理学化学环境科学与生态学计算机科学教育学经济学农林科学人文科学生物学数学物理与天体物理心理学综合性期刊其他工业工程理学历史学农学文学信息工程

数据库

全部 ACS Publications Elsevier ieeexplore Springer The Royal Society of Chemistry Wiley

期刊

Open Systems & Information Dynamics

全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.

﹀