Enhanced UV light detection using wavelength-shifting properties of Silicon nanoparticles

TL;DR

This paper demonstrates that silicon nanoparticles can be used as wavelength-shifting materials to enhance UV light detection, improving sensor response at wavelengths below 320 nm in particle physics experiments.

Contribution

It introduces the use of silicon nanoparticles as effective UV wavelength-shifters, enabling improved detection of UV photons with existing visible-range sensors.

Findings

Silicon nanoparticles absorb UV light around 200 nm.

Nanoparticle films shift UV light to visible wavelengths.

Sensor response is significantly enhanced below 320 nm.

Abstract

Detection of UV photons is becoming increasingly necessary with the use of noble gases and liquids in elementary particle experiments. Cerenkov light in crystals and glasses, scintillation light in neutrino, dark matter, and rare decay experiments all require sensitivity to UV photons. New sensor materials are needed that can directly detect UV photons and/or absorb UV photons and re-emit light in the visible range measurable by existing photosensors. It has been shown that silicon nanoparticles are sensitive to UV light in a wavelength range around ~200 nm. UV light is absorbed and re-emitted at wavelengths in the visible range depending on the size of the nanoparticles. Initial tests of the wavelength-shifting properties of silicon nanoparticles are presented here that indicate by placing a film of nanoparticles in front of a standard visible-wavelength detecting photosensor, the response of the sensor is significantly enhanced at wavelengths < 320 nm.