The second law of thermodynamics under unitary evolution and external operations
Files
Published version
Date
2015-03-01
Authors
Ikeda, Tatsuhiko N.
Sakumichi, Naoyuki
Polkovnikov, Anatoli
Ueda, Masahito
Version
Accepted manuscript
OA Version
Citation
Tatsuhiko N Ikeda, Naoyuki Sakumichi, Anatoli Polkovnikov, Masahito Ueda. 2015. "The second law of thermodynamics under unitary evolution and external operations." ANNALS OF PHYSICS, Volume 354, pp. 338 - 352 (15). https://doi.org/10.1016/j.aop.2015.01.003
Abstract
The von Neumann entropy cannot represent the thermodynamic entropy of equilibrium pure states in isolated quantum systems. The diagonal entropy, which is the Shannon entropy in the energy eigenbasis at each instant of time, is a natural generalization of the von Neumann entropy and applicable to equilibrium pure states. We show that the diagonal entropy is consistent with the second law of thermodynamics upon arbitrary external unitary operations. In terms of the diagonal entropy, thermodynamic irreversibility follows from the facts that quantum trajectories under unitary evolution are restricted by the Hamiltonian dynamics and that the external operation is performed without reference to the microscopic state of the system.