A thermodynamic approach to optimization in complex quantum systems

• URL: http://arxiv.org/abs/2305.06008v2
• Date: Thu, 28 Mar 2024 10:48:12 GMT
• Title: A thermodynamic approach to optimization in complex quantum systems
• Authors: Alberto Imparato, Nicholas Chancellor, Gabriele De Chiara,
• Abstract summary: We show that the optimal cooling is obtained in a regime where the bath exhibits a quantum phase transition in the thermodynamic limit. While this protocol does not destroy coherence in the system of interest, we show that it can further enhance the cooling effect.
• Score: 0.6144680854063939
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We consider the problem of finding the energy minimum of a complex quantum Hamiltonian by employing a non-Markovian bath prepared in a low energy state. The energy minimization problem is thus turned into a thermodynamic cooling protocol in which we repeatedly put the system of interest in contact with a colder auxiliary system. By tuning the internal parameters of the bath, we show that the optimal cooling is obtained in a regime where the bath exhibits a quantum phase transition in the thermodynamic limit. This result highlights the importance of collective effects in thermodynamic devices. We furthermore introduce a two-step protocol that combines the interaction with the bath with a measure of its energy. While this protocol does not destroy coherence in the system of interest, we show that it can further enhance the cooling effect.

Related papers

• Unveiling coherent dynamics in non-Markovian open quantum systems: exact expression and recursive perturbation expansion [44.99833362998488]
  We introduce a systematic framework to derive the effective Hamiltonian governing the coherent dynamics of non-Markovian open quantum systems.<n>Applying our framework to paradigmatic spin systems, we reveal how environmental correlations influence energy shifts and eigenbasis rotations.
  arXiv  Detail & Related papers  (2025-06-04T15:55:22Z)
• Thermalization of finite complexity and its application to heat bath algorithmic cooling [0.0]
  We introduce a class of thermal operations based on the collision model.<n>We identify a necessary condition for cooling below the bath temperature via a single collision.<n>We demonstrate that sub-bath cooling is achievable without a machine under these restricted thermal operations.
  arXiv  Detail & Related papers  (2025-05-15T07:57:16Z)
• Towards ultrastrong-coupling quantum thermodynamics using a superconducting flux qubit [3.439115146212617]
  We show experimental evidence of strong coupling by observing a hybridized state of the qubit with the cavities coupled to it. We also demonstrate close to 100% on-off ratio switching of heat current by applying small magnetic flux to the qubit. We provide a new tool for quantum thermodynamics aimed at realizing true quantum heat engines and refrigerators with enhanced power and efficiency.
  arXiv  Detail & Related papers  (2024-11-16T11:20:05Z)
• 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. 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)
• Pseudomode treatment of strong-coupling quantum thermodynamics [0.0]
  The evaluation of thermodynamic quantities in strong-coupling regimes requires a nonperturbative knowledge of the bath dynamics. We derive expressions for heat, work, and average system-bath interaction energy that only involve the autocorrelation function of the bath. We show in particular that this method allows for an efficient numerical evaluation of thermodynamic quantities.
  arXiv  Detail & Related papers  (2024-07-25T09:11:45Z)
• Quantum thermodynamics of the spin-boson model using the principle of minimal dissipation [41.94295877935867]
  We investigate the influence of the environment on quantities such as work, heat and entropy production. The results reveal significant differences to the weak-coupling forms of work, heat and entropy production.
  arXiv  Detail & Related papers  (2024-04-18T12:11:18Z)
• Thermodynamics of adiabatic quantum pumping in quantum dots [50.24983453990065]
  We consider adiabatic quantum pumping through a resonant level model, a single-level quantum dot connected to two fermionic leads. We develop a self-contained thermodynamic description of this model accounting for the variation of the energy level of the dot and the tunnelling rates with the thermal baths.
  arXiv  Detail & Related papers  (2023-06-14T16:29:18Z)
• Impurity reveals distinct operational phases in quantum thermodynamic cycles [23.09629129922603]
  impurity unlocks new operational phases in the system, such as a quantum heat engine, quantum refrigerator, and quantum cold pump. The cooling power and coefficient of performance of the quantum refrigerator and quantum cold pump are non-trivially affected by the impurity.
  arXiv  Detail & Related papers  (2022-07-06T13:01:06Z)
• 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)
• Open quantum systems at finite temperature [0.0]
  consistent definition of the thermodynamic functions of small open quantum systems in contact with an environment in equilibrium with a heat bath has been the subject of many debates in the quantum community. This approach overcomes the controversial discussions generated by the coupling between a system and its environment for any type of coupling between the two parts and allows for a consistent description of the thermodynamical properties of the system strongly interacting with the bath.
  arXiv  Detail & Related papers  (2020-10-29T06:53:40Z)

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.