Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5493383 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2017 | 4 Pages |
Abstract
Experiments seeking to detect rare event interactions such as dark matter or coherent elastic neutrino nucleus scattering are striving for large mass detectors with very low detection threshold. Using Neganov-Luke phonon amplification effect, the Cryogenic Dark Matter Search (CDMS) experiment is reaching unprecedented RMS resolutions of â¼14Â eVee. CDMSlite is currently the most sensitive experiment to WIMPs of mass â¼5Â GeV/c2 but is limited in achieving higher phonon gains due to an early onset of leakage current into Ge crystals. The contact interface geometry is particularly weak for blocking hole injection from the metal, and thus a new design is demonstrated that allows high voltage bias via vacuum separated electrode. With an increased bias voltage and aÃ2 Luke phonon gain, world best RMS resolution of sigma â¼7Â eVee for 0.25Â kg (d=75Â mm, h=1Â cm) Ge detectors was achieved. Since the leakage current is a function of the field and the phonon gain is a function of the applied voltage, appropriately robust interface blocking material combined with thicker substrate (25Â mm) will reach a resolution of â¼2.8Â eVee. In order to achieve better resolution of â¼ eV, we are investigating a layer of insulator between the phonon readout surface and the semiconductor crystals.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
Nader Mirabolfathi, H. Rusty Harris, Rupak Mahapatra, Kyle Sundqvist, Andrew Jastram, Bruno Serfass, Dana Faiez, Bernard Sadoulet,