Speaker
Description
Silicon photomultipliers (SiPMs) are increasingly important photosensors in rare-event and low-background experiments, including dark matter and neutrino detector programs, due to their high gain, compactness, improved radiopurity relative to PMTs, and single-photon resolution. As these experiments demand lower thresholds and improved background rejection, a more detailed understanding of SiPMs becomes increasingly valuable for both detector optimization and future sensor development.
In this work, two-photon absorption (TPA) is proposed as a characterization tool for studying SiPMs through mapping, performance measurement, and device diagnostics. Unlike conventional single-photon absorption, TPA preferentially produces carriers near the focal point within silicon, offering a promising route to probe internal device structure and spatially dependent avalanche behavior. This makes it well suited for investigating how the sensor response is influenced by local electric field conditions, absorption location, and device architecture.
The method is first established using a silicon photodiode, where TPA-induced signals are characterized through spatial scans and optical-intensity studies. The study then extends this approach to SiPMs, focusing on optical power and wavelength dependence, with future extensions potentially including polarization dependence and three-photon absorption.
By developing TPA as a method for SiPM characterization, this work aims to contribute to the broader effort to understand and improve photosensors used in dark matter and neutrino detector applications. This effort may help inform sensor selection, operating strategies, and future device design for astroparticle instrumentation.
| umadaan@triumf.ca | |
| Affiliation | TRIUMF |
| Research Theme | Dark Matter |