Quantum Ergotropy and Quantum Feedback Control

Abstract

We study the energy extraction from and charging to a finite-dimensional quantum system by general quantum operations. We prove that the changes in energy induced by unital quantum operations are limited by the ergotropy/charging bound for unitary quantum operations. This implies that, in order to break the ergotropy/charging bound for unitary quantum operations, one needs to perform a quantum operation with feedback control. We also show that the ergotropy/charging bound for unital quantum operations, applied to initial thermal equilibrium states, is tighter than the inequality representing the standard second law of thermodynamics without feedback control.

11 pages, 7 figures

References in corpus (6)

• Fluctuation theorems: Work is not an observable
• The Physics of Maxwell's demon and information
• Second Law of Thermodynamics with Discrete Quantum Feedback Control
• The role of quantum measurement in stochastic thermodynamics
• Correlation approach to work extraction from finite quantum systems
• A quantum Szilard engine without heat from a thermal reservoir