<title>Intrinsic 1/f noise in doped silicon thermistors for cryogenic calorimeters</title>

Abstract

We have characterized the intrinsic 1/f noise of ion- implanted silicon thermistors in the 0.05-0.5 K temperature range. This noise can have a significant effect on detector performance and needs to be taken into account in the design optimization of IR bolometers and x-ray microcalorimeters. The noise can be reasonably well fit as (Delta) R/R fluctuations whose spectral density varies as 1/f and increases steeply with lower doping density and lower temperatures. The observed 1/f noise can be approximated as a resistance fluctuations.