Informational work storage in quantum thermodynamics

Abstract

We present a critical examination of the difficulties with the quantum versions of a lifted weight that are widely used as work storage systems in quantum thermodynamics. To overcome those difficulties, we turn to the strong connections between information and thermodynamics illuminated by Szilard's engine and Landauer's principle, and consider the concept of informational work storage. This concept is in sharp contrast with the usual one of mechanical work storage underlying the idealization of a quantum weight. An informational work storage system based on maximally mixed qubits that does not act as an entropy sink and is capable of truly distinguishing work from heat is studied. Applying it to the problem of single-shot work extraction in various extraction schemes, we show that for a given system state the maximum extractable work is independent of extraction scheme, in accordance with the second law of thermodynamics.

11 pages, 2 figures, published version

References in corpus (8)

• Fluctuation theorems: Work is not an observable
• Description of quantum coherence in thermodynamic processes requires constraints beyond free energy
• The Physics of Maxwell's demon and information
• The thermodynamic meaning of negative entropy
• Observing a quantum Maxwell demon at work
• Non-equilibrium quantum fluctuations of work
• From single-shot to general work extraction with bounded fluctuations in work
• Single-shot work extraction in quantum thermodynamics revisited