12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Energy-dependent kinetic model of photon absorp...
View graph of relations

« Back

Energy-dependent kinetic model of photon absorption by superconducting tunnel junctions.

Research output: Contribution to journalJournal article

Published

Journal publication date1/11/2003
JournalJournal of Applied Physics
Journal number9
Volume94
Number of pages12
Pages5854-5865
Original languageEnglish

Abstract

We describe a model for photon absorption by superconducting tunnel junctions in which the full energy dependence of all the quasiparticle dynamic processes is included. The model supersedes the well-known Rothwarf–Taylor approach, which becomes inadequate for a description of the small gap structures that are currently being developed for improved detector resolution and responsivity. In these junctions relaxation of excited quasiparticles is intrinsically slow so that the energy distribution remains very broad throughout the whole detection process. By solving the energy-dependent kinetic equations describing the distributions, we are able to model the temporal and spectral evolution of the distribution of quasiparticles initially generated in the photoabsorption process. Good agreement is obtained between the theory and experiment.