Photo: Fermilab
The crystals are arranged in towers and have 1000 sensors on each side to detect energy from particle interactions.
Because the crystals themselves create some amount of thermal noise (the molecules in solid-state matter are constantly vibrating), the experiment is operated at extremely low temperatures - at 15 milliKelvin. Keeping the detectors this cold reduces the thermal noise as much as possible.
Learn more about SuperCDMS on the collaboration website