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Title: Quantum and Classical Ergotropy from Relative Entropies
The quantum ergotropy quantifies the maximal amount of work that can be extracted from a quantum state without changing its entropy. Given that the ergotropy can be expressed as the difference of quantum and classical relative entropies of the quantum state with respect to the thermal state, we define the classical ergotropy, which quantifies how much work can be extracted from distributions that are inhomogeneous on the energy surfaces. A unified approach to treat both quantum as well as classical scenarios is provided by geometric quantum mechanics, for which we define the geometric relative entropy. The analysis is concluded with an application of the conceptual insight to conditional thermal states, and the correspondingly tightened maximum work theorem.  more » « less
Award ID(s):
2010127
NSF-PAR ID:
10301549
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Entropy
Volume:
23
Issue:
9
ISSN:
1099-4300
Page Range / eLocation ID:
1107
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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