Landauer's principle in the quantum domain

Recent papers discussing thermodynamic processes in strongly coupled quantum systems claim a violation of Landauer's principle and imply a violation of the second law of thermodynamics. If true, this would have powerful consequences. Perpetuum mobiles could be build as long as the operating temperature is brought close to zero. It would also have serious consequences on thermodynamic derivations of information theoretic results, such as the Holevo bound. Here we argue why these claims are erroneous. Correlations occurring in the strongly coupled, quantum domain require a rethink of how entropy, heat and work are calculated. It is shown that a consistent treatment solves the paradox

Validity of Landauer's principle in the quantum regime

We demonstrate the validity of Landauer's erasure principle in the strong coupling quantum regime by treating the system-reservoir interaction in a consistent way. We show that the initial coupling to the reservoir modifies both energy and entropy of the system and provide explicit expressions for the latter in the case of a damped quantum harmonic oscillator. These contributions are related to the Hamiltonian of mean force and dominate in the strong damping limit. They need therefore to be fully taken into account in any low-temperature thermodynamic analysis of quantum systems.Comment: 4 pages, 2 figure

Alternativen zur Zinkphosphatierung: Vielversprechende Ergebnisse mit Dünnschichtvorbehandlungen auf Basis von Zirkonoxid

Im Rahmen eines Forschungsprojekts untersuchte das Fraunhofer IPA jetzt alternative Vorbehandlungen zur Zinkphosphatierung. Hierbei wurden zwei neue Zirkonoxid-basierte Vorbehandlungen auf Stahl-, verzinkten Stahl- und Aluminiumwerkstoffen im Vergleich zu einer marktüblichen Trikation-Zinkphosphatierung als Benchmark geprüft