Luminescence of BaBrI and SrBrI single crystals doped with Eu2+

TL;DR

This study investigates the luminescence properties and electronic structure of Eu$^{2+}$-doped BaBrI and SrBrI crystals, combining experimental spectra with advanced ab initio calculations to understand their electronic states and energy transitions.

Contribution

It provides new experimental data on emission and excitation spectra and employs GW calculations to analyze the electronic structure of Eu$^{2+}$-doped BaBrI and SrBrI crystals.

Findings

Determined the Eu$^{2+}$ 4f-5d transition energies.

Measured the band gaps of BaBrI and SrBrI.

Constructed vacuum-referred binding energy diagrams.

Abstract

The crystal growth procedure and luminescence properties of pure and Eu$^{2+}$-doped BaBrI and SrBrI crystals are reported. Emission and excitation spectra were recorded under ultraviolet and vacuum ultraviolet excitations. The energy of the first Eu$^{2+}$ 4f-5d transition and SrBrI band gap are obtained. The electronic structure calculations were performed within GW approximation as implemented in the Vienna Ab Initio Simulation Package. The energy between lowest Eu$^{2+}$ 5d state and the bottom of conduction band are found based on luminescence quenching parameters. The vacuum referred binding energy diagram of lanthanide levels was constructed using the chemical shift model.