The relaxation times of an STJ detector: Role of the proximity effect

The behavior of a superconducting tunnel junction detector (STJ) in the regime of low excitation is described, and the characteristic times of the dynamical response are discussed. The effect of a proximity layer in the STJ is analyzed in terms of the McMillan model. A set of phenomenological equations for the proximized STJ driven out of equilibrium is obtained, showing the importance of the role of the proximity effect in the dynamics of the device.