Foundations of quantum thermodynamics

• Applicants: Professor Dr. Eric Lutz; Professor Dr. Kilian Singer
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas ; Experimental Condensed Matter Physics
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 384846402

The standard paradigm of thermodynamics is that of a system weakly coupled to a thermal reservoir. The two central quantities of the theory are work and heat from which entropy and free energies can be derived. The second law for the entropy then plays a pivotal role in limiting the amount of useful work that may be extracted from the system. Lately, these very foundations of thermodynamics have been challenged in the quantum regime. Key assumptions such as weak coupling, thermal reservoirs, Gibbs distribution and a unique entropy have been challenged and relaxed. Furthermore, conceptual issues such as how to properly theoretically define and experimentally measure work and heat in the quantum regime have emerged. It is fair to say that none of these problems have been satisfactorily solved today.This project will set out to formulate a concise theory of quantum thermodynamics, bringing together a wide range of pictures and mindsets that were formulated recently. It hence aims at settling the foundations on which this Research Unit rests.

• DFG Programme: Research Units
• Subproject of: FOR 2724: Thermal machines in the quantum world
• Major Instrumentation: Narrow-linewidth tapered amplifier laser system, with reference cavity
• Instrumentation Group: 5700 Festkörper-Laser