We investigated charge transport in an n-type germanium detector at 5.2 K to
explore new technology for enhancing low-mass dark matter detection
sensitivity. Calculations of dipole and cluster dipole state binding energies
and electric field-dependent trapping cross-sections are critical to developing
low-threshold detectors. The detector operates in two modes: depleting at 77K
before cooling, or directly cooling to 5.2 K and applying different bias
voltages. Results indicated lower binding energy of charge states in the second
mode, at zero field and under an electric field, suggesting different charge
states formed under different operating modes. Measured cluster dipole and
dipole state binding energies at zero field were 7.884±0.644 meV and
8.369±0.748 meV, respectively, signifying high low-threshold potential for
low-mass dark matter searches in the future.Comment: 7 pages, 8 figure