Hot Carrier Velocities in Doped and in Ultra-pure Germanium Crystals at Millikelvin Temperatures
The velocity laws of electrons and holes in germanium single crystals at millikelvin temperatures are determined as a function of the electric field in the 〈001〉 orientation, based on time-of-flight measurements in cryogenic coplanar grid Ge detectors. Results obtained in two n-type crystals (|N a −N d |<1010 cm−3 and doped to 1011 cm−3) are compared with the experimental data from previous investigations, and shown to be consistent with Monte-Carlo simulations of carrier transport.
KeywordsDark matter search Germanium cryogenic detectors Time-of-flight measurements Hot carriers transport
This study has been supported in part by Agence Nationale pour la Recherche under contract ANR-2010-BLAN-0422 02.