Comparison of Ce$^{3+}$ and Pr$^{3+}$ activators in alkaline-earth fluoride crystals

TL;DR

This study compares Ce$^{3+}$ and Pr$^{3+}$ activators in alkaline-earth fluoride crystals, analyzing their excitation and emission spectra to understand energy transfer mechanisms under VUV and X-ray excitation.

Contribution

It provides a detailed comparison of Ce$^{3+}$ and Pr$^{3+}$ activators, revealing distinct excitation processes and energy transfer stages in alkaline-earth fluorides.

Findings

Ce$^{3+}$ excitation mainly involves exciton energy transfer.

Pr$^{3+}$ exhibits two excitation processes: slow f-f and fast d-f luminescence.

Three stages of energy transfer were identified for Ce$^{3+}$.

Abstract

The emission spectra of Ce$^{3+}$ or Pr$^{3+}$ doped CaF$_2$, SrF$_2$, BaF$_2$ excited by vacuum ultraviolet photons or by x-ray as well as excitation and absorption spectra in vacuum ultraviolet region (6-13 eV) were studied. The transfer of exciton energy is the main channel for Ce$^{3+}$ excitation in alkaline-earth fluorides. Three different stages of energy transfer were observed. Pr$^{3+}$ excited by two processes, slow f-f luminescence excited by excitons, fast d-f luminescence excited by some fast process.