Cryogenic Detector Development For Direct Dark Matter Search

We are developing massive cryogenic detectors with low energy thresholds and high resolution for use in a direct Dark Matter search experiment. Our detector consists of a superconducting phase transition thermometer evaporated onto the surface of an absorber crystal. An energy resolution of 220 eV FWHM (for 6 keV X-rays) has been reached with a 31 g sapphire crystal using a proximity-effect thermometer. The latest results for sapphire detectors using tungsten superconducting phase transition thermometers, whose development is just beginning, are also presented. The planned further development and use of such detectors in a search for Dark Matter particles (WIMPs) is discussed, showing their advantages for low WIMP masses.