Asymmetries of thermal processes in open quantum systems

• URL: http://arxiv.org/abs/2406.19829v2
• Date: Mon, 07 Apr 2025 22:02:53 GMT
• Title: Asymmetries of thermal processes in open quantum systems
• Authors: Álvaro Tejero, Rafael Sánchez, Laiachi El Kaoutit, Daniel Manzano, Antonio Lasanta,
• Abstract summary: We show that the free relaxation to thermal equilibrium follows intrinsically different paths depending on whether it involves the temperature of the system to increase or to decrease.<n>A general understanding is obtained based on the spectral decomposition of the Liouvillian and the spectral gap of reciprocal processes.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: An intriguing phenomenon in non-equilibrium quantum thermodynamics is the asymmetry of thermal processes. Relaxation to thermal equilibrium is the most important dissipative process, being a key concept for the design of heat engines and refrigerators, contributing to the study of foundational questions of thermodynamics, and being relevant for quantum computing through the process of algorithmic cooling. Despite their importance, the dynamics of these processes are far from being understood. We show that the free relaxation to thermal equilibrium follows intrinsically different paths depending on whether it involves the temperature of the system to increase or to decrease. Our theory is exemplified using the recently developed thermal kinematics based on information geometry theory, utilizing three prototypical examples: a two-level system, the quantum harmonic oscillator, and a trapped quantum Brownian particle, in all cases showing faster heating than cooling under the appropriate conditions. A general understanding is obtained based on the spectral decomposition of the Liouvillian and the spectral gap of reciprocal processes.

Related papers

• Heat operator approach to quantum stochastic thermodynamics in the strong-coupling regime [0.0]
  We identify a 'heat operator,' whose moments with respect to the vacuum state correspond to the moments of the heat exchanged with a thermal bath. This recasts the statistics of heat statistics as a standard unitary time-evolution problem. We exploit the chain mapping of thermodynamic reservoirs to compute heat fluctuations in the Ohmic spin-boson model.
  arXiv  Detail & Related papers  (2025-04-14T18:26:45Z)
• 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. 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)
• A novel scheme for modelling dissipation or thermalization in open quantum systems [0.0]
  We introduce a novel method for investigating dissipation (gain) and thermalization in an open quantum system. To demonstrate the efficiency and significance of the method, we apply it to some ubiquitous open quantum systems.
  arXiv  Detail & Related papers  (2024-04-16T05:20:30Z)
• Quantum Fisher Information for Different States and Processes in Quantum Chaotic Systems [77.34726150561087]
  We compute the quantum Fisher information (QFI) for both an energy eigenstate and a thermal density matrix. We compare our results with earlier results for a local unitary transformation.
  arXiv  Detail & Related papers  (2023-04-04T09:28:19Z)
• On the First Law of Thermodynamics in Time-Dependent Open Quantum Systems [0.0]
  How to rigorously define thermodynamic quantities such as heat, work, and internal energy in open quantum systems driven far from equilibrium remains a significant open question in quantum thermodynamics. Heat is a quantity whose fundamental definition applies only to processes in systems infinitesimally perturbed from equilibrium. Heat is accounted for carefully in strongly-driven systems.
  arXiv  Detail & Related papers  (2022-08-13T02:26:31Z)
• 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)
• Implementation of a two-stroke quantum heat engine with a collisional model [50.591267188664666]
  We put forth a quantum simulation of a stroboscopic two-stroke thermal engine in the IBMQ processor. The system consists of a quantum spin chain connected to two baths at their boundaries, prepared at different temperatures using the variational quantum thermalizer algorithm.
  arXiv  Detail & Related papers  (2022-03-25T16:55:08Z)
• Fast Thermalization from the Eigenstate Thermalization Hypothesis [69.68937033275746]
  Eigenstate Thermalization Hypothesis (ETH) has played a major role in understanding thermodynamic phenomena in closed quantum systems. This paper establishes a rigorous link between ETH and fast thermalization to the global Gibbs state. Our results explain finite-time thermalization in chaotic open quantum systems.
  arXiv  Detail & Related papers  (2021-12-14T18:48:31Z)
• 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)
• Relating Heat and Entanglement in Strong Coupling Thermodynamics [0.0]
  We develop a new approach to study thermodynamics in the strong coupling regime. We apply the method to calculate the time-dependent thermodynamic properties of a system and an environment. The results indicate that the transient imbalance between heat dissipated and heat absorbed is responsible for the generation of system-environment entanglement.
  arXiv  Detail & Related papers  (2021-04-13T05:36:21Z)
• Taking the temperature of a pure quantum state [55.41644538483948]
  Temperature is a deceptively simple concept that still raises deep questions at the forefront of quantum physics research. We propose a scheme to measure the temperature of such pure states through quantum interference.
  arXiv  Detail & Related papers  (2021-03-30T18:18:37Z)
• 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)
• Quantum thermodynamically consistent local master equations [0.0]
  We show that local master equations are consistent with thermodynamics and its laws without resorting to a microscopic model. We consider a quantum system in contact with multiple baths and identify the relevant contributions to the total energy, heat currents and entropy production rate.
  arXiv  Detail & Related papers  (2020-08-11T14:53:36Z)
• Simulating finite-time quantum isothermal processes with generic superconducting quantum circuit [7.925489596652414]
  We provide a discrete-step method to separate the work done and the heat exchange in the isothermal process. The piecewise control scheme makes it possible to simulate the whole process on a generic quantum computer. We implement the simulation on ibmqx2 to show the $mathrmmathcalC/tau$ scaling of the extra work in the finite-time isothermal process.
  arXiv  Detail & Related papers  (2020-03-25T08:31:45Z)
• Thermodynamics of Optical Bloch Equations [0.0]
  We study the coherent exchange of energy between a quantum bit (qubit) and a quasi-resonant driving field in the presence of a thermal bath. We coarse-grain the obtained expressions, using a methodology similar to the derivation of the dynamical master equation. Our findings can be readily extended to larger open quantum systems.
  arXiv  Detail & Related papers  (2020-01-22T14:37:05Z)
• Simulation of Thermal Relaxation in Spin Chemistry Systems on a Quantum Computer Using Inherent Qubit Decoherence [53.20999552522241]
  We seek to take advantage of qubit decoherence as a resource in simulating the behavior of real world quantum systems. We present three methods for implementing the thermal relaxation. We find excellent agreement between our results, experimental data, and the theoretical prediction.
  arXiv  Detail & Related papers  (2020-01-03T11:48:11Z)

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.