Your browser has javascript turned off or blocked. This will lead to some parts of our website to not work properly or at all. Turn on javascript for best performance.

The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

picture of me

Patrick Potts

Postdoctoral fellow

picture of me

Optimal work extraction from quantum states by photo-assisted Cooper pair tunneling

Author

  • Niels Lörch
  • Christoph Bruder
  • Nicolas Brunner
  • Patrick P. Hofer

Summary, in English

The theory of quantum thermodynamics predicts fundamental bounds on work extraction from quantum states. As these bounds are derived in a very general and abstract setting, it is unclear how relevant they are in an experimental context, where control is typically limited. Here we address this question by showing that optimal work extraction is possible for a realistic engine. The latter consists of a superconducting circuit, where a LC-resonator is coupled to a Josephson junction. The oscillator state fuels the engine, providing energy absorbed by Cooper pairs, thus producing work in the form of an electrical current against an external voltage bias. We show that this machine can extract the maximal amount of work from all Gaussian and Fock states. Furthermore, we consider work extraction from a continuously stabilized oscillator state. In both scenarios, coherence between energy eigenstates is beneficial, increasing the power output of the machine. This is possible because the phase difference across the Josephson junction provides a phase reference.

Department/s

  • Mathematical Physics
  • NanoLund

Publishing year

2018-06-27

Language

English

Publication/Series

Quantum Science and Technology

Volume

3

Issue

3

Document type

Journal article

Publisher

Institute of Physics Publishing

Topic

  • Physical Sciences

Keywords

  • inelastic cooper pair tunneling
  • mesoscopic physics
  • quantum thermodynamics
  • resource theory
  • work extraction

Status

Published

ISBN/ISSN/Other

  • ISSN: 2058-9565