# Thermoluminescence properties and new insights on the UV-vis absorption features of colorless quartz after γ-ray irradiation

## TL;DR

This study explores how gamma-ray irradiation affects the thermoluminescence and UV-vis absorption properties of colorless quartz, revealing new insights into the behavior of electron traps and absorption centers.

## Contribution

The paper provides new insights into the relationship between thermoluminescence glow peaks and absorption centers in quartz after gamma irradiation.

## Key findings

- Thermally stimulated conductivity measurements identified electron-hole recombination mechanisms across various temperature ranges.
- Nonlinearity and signal saturation in thermoluminescence were observed at specific dose thresholds for different electron traps.
- Irradiation and heat treatment influence the formation of absorption centers, which are linked to electronic traps.

## Abstract

In this paper, we present the results of research on the thermoluminescence (TL) and optical absorption (OA) properties of colorless natural quartz (including natural quartz samples, sodium ion (Na+) rich samples (by diffusion), and alkali metal (M+) ion poor samples (by sweep)). In detail, the relationship between the TL glow peaks and the emission wavelength was determined. The dynamics parameters (ET, s, τ) have been computed for all TL peaks on the glow curve. The recombination mechanism electron–hole with the participation of the region energy has been determined for all electron traps in the temperature range of 50–430 °C through thermally stimulated conductivity measurement (TSC). Nonlinearity and approaching signal saturation are observed at doses above 22 Gy for the electron trap at 110 °C, above 45 Gy for the electron trap at 238 °C, and 80 Gy for the electron traps at 325 °C and 375 °C. The role of irradiation and heat treatment in the formation of absorption centers as well as the relationship of these centers to electronic traps have been also investigated in detail. The role of M+ ions and hydrogen ions (H+) for the absorption bands in the UV-vis region has been discussed. The results of the combination of the TL measurement and monochromatic light absorption according to temperature show that the TL process occurs concurrently with the reduction of the absorbent center produced in the irradiation process.

3-D TL spectrum (a) and contour plot (2D-TL) of the emission spectrum (b) of the natural quartz (with the heating rate of β = 5 °C s−1, γ-ray irradiation Dγ = 6.4 Gy).