Electroluminescence and charge multiplication in liquid xenon with a VCC-like Microstrip Plate

TL;DR

This paper reports the first observation of electroluminescence and charge amplification in liquid xenon using a VCC microstrips plate, highlighting its potential for advanced noble-liquid detectors in physics research.

Contribution

It introduces a novel VCC microstrips plate in liquid xenon, demonstrating electroluminescence and charge amplification, and discusses stability and future improvements.

Findings

Initial light yield of ~460 VUV photons per electron

Stabilized light yield of 27 photons per electron

Charge gain estimated to be less than 10

Abstract

We report on the first observation of electroluminescence and charge amplification with a Virtual Cathode Chamber (VCC) microstrips plate immersed in liquid xenon. Both were observed in an intense non-uniform electric field in the vicinity of 2-$\mu$m narrow anode strips deposited, with a 2~mm pitch, on a semiconductive glass substrate (S8900), with a cathode film on its backside. An initial light yield of $\sim$460 VUV photons per drifting electron was measured, which degraded within tens of minutes stabilizing at (27.0~$\pm$~3.1)~photons per electron. The electroluminescence was accompanied by electron multiplication with an estimated charge gain $<$10. Further investigations are necessary to understand and mitigate the light yield degradation phenomenon. We expect other substrate materials, including VUV-transparent ones, to provide large stable photon yields, compatible with our model predictions. The VCC configuration has demonstrated great potential in single-phase noble-liquid detectors, particularly for dark-matter searches, neutrino physics and other fields.