Parts | Days | Selection | Search | Updates | Downloads | Help
QI: Fachverband Quanteninformation
QI 11: Quantum Thermodynamics
QI 11.5: Talk
Tuesday, March 19, 2024, 10:45–11:00, HFT-TA 441
Thermodynamic concepts in autonomous quantum systems — •Anja Seegebrecht and Tanja Schilling — University Freiburg, Freiburg, Germany
Physically sound definitions of thermodynamic quantities for open quantum systems pose a challenge. They are at best available for the weak coupling regime where the reduced dynamics can be described by Markov master equations. To extend concepts like internal energy, work and heat to processes with strong interactions and memory effects, the canonical form of the time-convolutionless master equation offers a promising possibility. This unique time-local representation has Lindblad-like structure with a Hamiltonian and a dissipator. It is obtained by minimisation of the dissipative part of the dynamics. Accordingly, it characterizes the dissipation and non-Markovianity. The identification of thermodynamic energies follows the typical method that internal energy is the expectation value of the effective Hamiltonian of the system. Changes of this local energy can be split into a part that relates to entropy variation and a part that does not, namely heat and work contributions. We contrast the minimal dissipation definition with three different approaches for autonomous systems. They are also based on this strategy but propose different decompositions of the dynamics. The comparison highlights the benefits of the canonical form.
Keywords: canonical master equation; work; heat; stong interaction