近日，巴西弗鲁米嫩塞联邦大学的M. S. Sarandy等人合作取得一项新进展。经过不懈努力，他们揭示了功剩余度和环境诱导功的量子比特动力学。相关研究成果已于2024年5月16日在国际知名学术期刊《物理评论A》上发表。
该研究团队研究了开放系统在马尔可夫和非马尔可夫演化下的功剩余度动力学。在这种情况下，研究人员首先从能量和相干性的角度阐述任意量子比特态的自洽性。因此，研究人员确定了系统-浴相互作用导致的功剩余度冻结和功剩余度猝灭的条件。为了在开放系统场景中以功的形式利用功剩余度作为能量提取的资源，他们采用了基于熵的量子热力学公式。
在这种方法中，功获得了额外的环境诱导分量，即使对于恒定的哈密顿量也可能存在。然后，研究人员建立了环境诱导功与功剩余度之间的分析关系，从功剩余度变化的角度对环境诱导功进行了解释。特别是，由环境引起的功的能量转移可以进行到一个极限，这是由量子动力学的初始和最终被动态之间传递的能量成本决定的。研究人员举例说明了在非耗散和耗散量子过程下演化的量子比特态的结果。
附：英文原文
Title: Qubit dynamics of ergotropy and environment-induced work
Author: J. M. Z. Choquehuanca, P. A. C. Obando, F. M. de Paula, M. S. Sarandy
Issue&Volume: 2024/05/16
Abstract: We investigate the dynamics of ergotropy in open systems under Markovian and non-Markovian evolutions. In this scenario, we begin by formulating the ergotropy of an arbitrary qubit state in terms of energy and coherence. Thus we determine the conditions for ergotropy freezing and ergotropy sudden death as a consequence of the system-bath interaction. In order to use ergotropy as a resource for energy extraction in the form of work in an open-system scenario, we adopt the entropy-based formulation of quantum thermodynamics. In this approach, the work gains an additional environment-induced component, which may be present even for constant Hamiltonians. We then establish an analytical relationship between the environment-induced work and ergotropy, providing an interpretation of environment-induced work in terms of variation of ergotropy. In particular, energy transfer by environment-induced work can be performed up to a limit, which is governed by the energy cost to transit between the initial and final passive states of the quantum dynamics. We illustrate these results for qubit states evolving under nondissipative and dissipative quantum processes.
DOI: 10.1103/PhysRevA.109.052219
Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.052219
