Book Description

This thesis describes design, fabrication, and characterizations of high-Tc transition edge sensor (TES) detectors aiming at cryogen-free infrared application. TES is a superconducting thermometer based bolometric detector, whose operating resistance is strongly dependent on temperature, and therefore shows much higher sensitivity than standard non-superconducting bolometers. This thesis starts from the overview of major infrared detectors, then discusses in detail the theoretical background of a TES detector and some important figures of merit in evaluating its performance. Some TES arrays that are currently in use or under development for astronomical, ground or space-based missions are reviewed. The core of this thesis is the design and fabrication process of a TES detector, which is presented as a live report in Chapter 3 and provides useful guide for future detector fabrication. In order to evaluate performance of our devices, a cryogen-free cryostat is used for testing and its operational mechanics is introduced. In the final part, the experimental configurations for different tests are delivered, and the figures of merit mentioned above are measured and used to characterize fabrication results.