학술논문

Photoelectric absorption cross section of silicon near the bandgap from room temperature to sub-Kelvin temperature
Document Type
article
Source
AIP Advances, Vol 11, Iss 2, Pp 025120-025120-6 (2021)
Subject
Physics
QC1-999
Language
English
ISSN
2158-3226
Abstract
The use of cryogenic silicon as a detector medium for dark matter searches is gaining popularity. Many of these searches are highly dependent on the value of the photoelectric absorption cross section of silicon at low temperatures, particularly near the silicon bandgap energy, where the searches are most sensitive to low mass dark matter candidates. While such cross section data have been lacking from the literature, previous dark matter search experiments have attempted to estimate this parameter by extrapolating it from higher temperature data. However, discrepancies in the high temperature data have led to order-of-magnitude differences in the extrapolations. In this paper, we resolve these discrepancies by using a novel technique to make a direct, low temperature measurement of the photoelectric absorption cross section of silicon at energies near the bandgap (1.2 eV–2.8 eV).