Formulations of Quantum Thermodynamics and Applications in Open Systems

• URL: http://arxiv.org/abs/2512.00923v1
• Date: Sun, 30 Nov 2025 15:00:38 GMT
• Title: Formulations of Quantum Thermodynamics and Applications in Open Systems
• Authors: J. M. Z. Choquehuanca,
• Abstract summary: We explore different ways to describe quantum thermodynamics, using two main approaches: one based on entropy and the other on ergotropy.<n>In this thesis, we introduce a generalized approach to quantify non-Markovianity through the breakdown of monotonicity in thermodynamic functions.<n>We identify phenomena such as freezing and sudden death of ergotropy, and we establish an analytical relation between the change in ergotropy and the environment-induced work.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Quantum thermodynamics has emerged as a central field for understanding how energy conversion processes occur in microscopic systems. In these systems, effects such as coherence, entanglement, and non-Markovianity play key roles. In this thesis, we explore different ways to describe quantum thermodynamics, using two main approaches: one based on entropy and the other on ergotropy. First, we introduce a generalized approach to quantify non-Markovianity through the breakdown of monotonicity in thermodynamic functions. In this context, the entropy-based heat flow serves as a practical tool to witness and measure quantum memory in unital maps that do not reverse the sign of the internal energy. Next, we analyze the dynamics of ergotropy in open qubits under both Markovian and non-Markovian evolutions. We identify phenomena such as freezing and sudden death of ergotropy, and we establish an analytical relation between the change in ergotropy and the environment-induced work . This provides a clear physical interpretation for the additional term in the first law in the entropy-based formulation. Finally, we propose an ergotropy-based thermodynamic formulation, in which heat is reinterpreted in terms of the change of the passive state associated with the density operator governing the quantum dynamics. This approach allows one to measure non-Markovianity of unital maps more generally and accurately than the entropy-based heat flow. This advantage comes from the direct link between heat and von Neumann entropy, a property ensured by invariance under passive transformations. Moreover, the out-of-equilibrium temperature naturally remains non-negative, similarly to equilibrium thermodynamics.

Related papers

• Quantum thermodynamics in nonequilibrium [0.0]
  We develop a first-principles framework for nonequilibrium quantum thermodynamics by integrating quantum resource theory of coherence with thermodynamic laws.<n>Applying the theory to an exactly solvable open quantum system, we reveal how equilibrium thermodynamics emerges dynamically in the weak-coupling limit.
  arXiv  Detail & Related papers  (2026-02-09T13:52:46Z)
• Ergotropy-Based Quantum Thermodynamics [0.0]
  We introduce an ergotropy-based formulation of quantum thermodynamics, which provides a strong connection between average heat and von Neumann entropy.<n>As an application, the average heat can be used as a general non-Markovinity measure for unital maps.
  arXiv  Detail & Related papers  (2025-04-09T18:26:51Z)
• Thermodynamic Roles of Quantum Environments: From Heat Baths to Work Reservoirs [49.1574468325115]
  Environments in quantum thermodynamics usually take the role of heat baths. We show that within the same model, the environment can take three different thermodynamic roles. The exact role of the environment is determined by the strength and structure of the coupling.
  arXiv  Detail & Related papers  (2024-08-01T15:39:06Z)
• Quantum Thermodynamics of Open Quantum Systems: Nature of Thermal Fluctuations [0.0]
  We investigate the thermodynamic behavior of open quantum systems through the Hamiltonian of Mean Force.<n>By analyzing both weak and strong coupling regimes, we uncover the impact of environmental interactions on quantum thermodynamic quantities.
  arXiv  Detail & Related papers  (2024-07-31T13:18:06Z)
• Non-Markovianity through entropy-based quantum thermodynamics [0.0]
  We propose a measure of non-Markovianity based on the heat flow for single-qubit quantum evolutions. This measure can be applied for unital dynamical maps that do not invert the sign of the internal energy.
  arXiv  Detail & Related papers  (2022-10-07T18:09:32Z)
• Gauge Quantum Thermodynamics of Time-local non-Markovian Evolutions [77.34726150561087]
  We deal with a generic time-local non-Markovian master equation. We define current and power to be process-dependent as in classical thermodynamics. Applying the theory to quantum thermal engines, we show that gauge transformations can change the machine efficiency.
  arXiv  Detail & Related papers  (2022-04-06T17:59:15Z)
• Open-system approach to nonequilibrium quantum thermodynamics at arbitrary coupling [77.34726150561087]
  We develop a general theory describing the thermodynamical behavior of open quantum systems coupled to thermal baths. Our approach is based on the exact time-local quantum master equation for the reduced open system states.
  arXiv  Detail & Related papers  (2021-09-24T11:19:22Z)
• Qubit thermodynamics far from equilibrium: two perspectives about the nature of heat and work in the quantum regime [68.8204255655161]
  We develop an alternative theoretical framework for the thermodynamic analysis of two-level systems. We observe the appearance of a new term of work, which represents the energy cost of rotating the Bloch vector in presence of the external field that defines the local Hamiltonian. In order to illustrate our findings we study, from both perspectives, matter-radiation interaction processes for two different systems.
  arXiv  Detail & Related papers  (2021-03-16T09:31:20Z)
• Entropy production in the quantum walk [62.997667081978825]
  We focus on the study of the discrete-time quantum walk on the line, from the entropy production perspective. We argue that the evolution of the coin can be modeled as an open two-level system that exchanges energy with the lattice at some effective temperature.
  arXiv  Detail & Related papers  (2020-04-09T23:18:29Z)
• Out-of-equilibrium quantum thermodynamics in the Bloch sphere: temperature and internal entropy production [68.8204255655161]
  An explicit expression for the temperature of an open two-level quantum system is obtained. This temperature coincides with the environment temperature if the system reaches thermal equilibrium with a heat reservoir. We show that within this theoretical framework the total entropy production can be partitioned into two contributions.
  arXiv  Detail & Related papers  (2020-04-09T23:06:43Z)
• Quantum thermodynamics of two bosonic systems [0.0]
  We study the energy exchange between two bosonic systems that interact via bilinear transformations in the mode operators. This work finds its roots in a very recent formulation of quantum thermodynamics.
  arXiv  Detail & Related papers  (2020-01-14T09:19:02Z)
• On the contribution of work or heat in exchanged energy via interaction in open bipartite quantum systems [0.0]
  We will use genuine reasoning based on which Clausius originally defined work and heat in establishing thermodynamics. It will be shown that these refined definitions will strongly affect the entropy production of quantum thermodynamic processes.
  arXiv  Detail & Related papers  (2019-12-04T13:52:46Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.