I am involved with various projects in the field of submillimetre astronomy.
Our group and collaborators have designed, built and operated some of the most sensitive bolometer systems in existence at these wavelength ranges. Traditionally, bolometers have been hand-built in small quatities using a composite design of thermally isolated radiation absorbers coupled to small semiconductor thermistors. The state of the art is now moving towards superconducting transition edge sensors (TES) and kinetic inductance detectors (KID) operating below 0.1 K, which have orders of magnitude higher sensitivity than earlier composite bolometers and lend themselves to lithographic fabrication in dense arrays. We are currently fabricating TES devices which, while they have much lower sensitivities than required by current space-bourne applications, can be operated at 4K using much simpler closed-cycle liquid cryogen-free coolers.