Intermediate states near normal-superconducting transition at ~100mK, important for a sensitive thermometer in x-ray calorimetry, have been studied by an imaging technique based on Low Temperature Scanning Synchrotron Microscopy (LTSSM). In conjunction with iridium superconducting transition-edge sensors operating in electrothermal feedback mode, the LTSSM visualizations reveal that a normal-superconducting phase separation takes place in the actual intermediate states.
@article{arxiv.cond-mat/0205035,
title = {Intermediate states of superconducting thermometers for x-ray microcalorimeters},
author = {H. Pressler and M. Koike and M. Ohkubo and D. Fukuda and Y. Noguchi and M. Ohno and H. Takahashi and M. Nakazawa},
journal= {arXiv preprint arXiv:cond-mat/0205035},
year = {2009}
}