Dissipation by surface states in superconducting radio-frequency cavities

  title={Dissipation by surface states in superconducting radio-frequency cavities},
  author={Sean Deyo and Michelle M. Kelley and Nathan S. Sitaraman and Thomas Oseroff and Danilo B. Liarte and Tomas Arias and Matthias U. Liepe and James P. Sethna},
  journal={Physical Review B},
Recent experiments on superconducting cavities have found that under large radio-frequency (RF) electromagnetic fields the quality factor can improve with increasing field amplitude, a so-called “anti- Q slope.” Linear theories of dissipation break down under these extreme conditions and are unable to explain this behavior. We numerically solve the Bogoliubov-de Gennes equations at the surface of a superconductor in a parallel AC magnetic field, finding that at large fields there are quasiparticle… 

Figures from this paper

The importance of the electron mean free path for superconducting radio-frequency cavities

Impurity-doping of niobium is an exciting new technology in the field of superconducting radio-frequency accelerators, producing cavities with record-high quality factor Q0 and

Non-equilibrium superconductivity in quantum-sensing superconducting resonators

Low temperature microwave superconducting resonators (SRs) are attractive candidates for producing quantum-sensitive, arrayable energy or power detectors for astrophysical and other precision

Frequency dependence of trapped flux sensitivity in SRF cavities

In this letter, we present the frequency dependence of the vortex surface resistance of bulk niobium accelerating cavities as a function of different state-of-the-art surface treatments. Higher flux

Introduction to Superconductivity

We have seen how the conductivity of a metal is limited by collisions, which determine the electron mean free path. After a collision, an electron completely loses all memory of its quantum state as

Nitrogen and argon doping of niobium for superconducting radio frequency cavities: a pathway to highly efficient accelerating structures

We report a surface treatment that systematically improves the quality factor of niobium radio frequency cavities beyond the expected limit for niobium. A combination of annealing in a partial

Imaging standing waves in a two-dimensional electron gas

ELECTRONS occupying surface states on the close-packed surfaces of noble metals form a two-dimensional nearly free electron gas1–3. These states can be probed using the scanning tunnelling microscope

50 years of success for SRF accelerators—a review

The past five decades have seen many successes in superconducting radio-frequency (SRF) enabling a variety of accelerators. These successes are the result of steady progress in understanding the