The use of quasiparticle diffusion in a superconducting film has the potential to allow an increase in the size of a cryogenic detector without proportional loss of energy resolution. The quasiparticle lifetime and the diffusion constant are critical parameters which have limited this development. Using W superconducting phase transition thermometers as the sensors and a W/Al bilayer as the diffusion film, we have measured quasiparticle diffusion over a distance of 2 mm and deduced a diffusion constant of D = 2.5 × 10-4 m2/s and a quasiparticle lifetime of τ = 9.0 ms, which is, to our knowledge, by far the longest ever observed. With Ir/Au thermometers and an Ir/Au/Al diffusion film we found D = 4.6 × 10-3 m2/s and τ = 0.43 ms with diffusion over 4 mm, the longest distance observed to date.
|Number of pages||7|
|Journal||Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment|
|Publication status||Published - jún. 11 2001|
ASJC Scopus subject areas
- Nuclear and High Energy Physics