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The Cryogenic Dark Matter Search (CDMS) is an experiment to detect dark-matter particles, i.e., WIMPs. It assumes the presumed particle interacts with baryonic matter, but does so very rarely, and it presumes that such an interaction produces a very tiny recoil. Such a recoil of electrons or nuclei can produce a detectable state of ionization. It operates cryogenically to minimize thermal effects. The recoil is sensed and measured by two types of devices: transition edge sensors (TESs) with SQUID amplifiers, and FETs (field-effect transistors). Also, material of two different elements, with different mass nuclei are monitored, silicon and germanium. The ratios of the detected types of reaction among the two elements reveal information about the particles causing the ionization, particular ratios fit the criteria of a WIMP, whereas various other known ratios would indicate interactions with known kinds of particles, such as neutrons.
The initial experiment was followed up by a new generation, the two versions of the experiment called CDMS I (late 1990s under Stanford campus) and CDMS II (2003-2008, in a deep mine at Soudan, Minnesota). Following that was SuperCDMS (aka SuperCDMS Soudan, 2011-2015) in the mine, which included an experiment CDMSlite, specifically looking for at light dark matter. Yet another attempt, SuperCDMS SNOLAB, plans to begin operation in 2023 at SNOLAB, a Canadian underground physics facility created at the location of the Sudbury Neutrino Observatory (SNO). Future plans include another SNOLAB experiment called GEODM (for Germanium Observatory for Dark Matter).
Results have included some candidate interactions and some limits on possible energies of the particles.