Optical properties of laser-active color centers

Electrolytic coloration of O22−-doped NaCl crystals

“…Today, it is well known that (F 2 + ) H color center in NaCl crystal host is a very good active center and can be produced by photo-and thermal-treating colored NaCl crystal doped with O 2 2À or OH À impurities [1][2][3]. A necessary condition for producing the (F 2 + ) H color center is that there is O 2À -V a + dipole or its complex in the crystal.…”

Probing the Structure and Dynamics of Na+ Ionic Doped LiF Crystals in Fluoride Eutectic Salt by Solid-State NMR

“…The color center lasers are solid-state lasers always based on alkali metal halide crystals, , which has a series of advantages such as high efficiency and high output power, low pump threshold, narrow line width, and tunable wavelength. , A considerable number of ionic doped crystals show excellent optical performance and are treated as the major choice of laser crystals. − For instance, the KCl–NaCl eutectic salt is an infinite solid solution from the phase diagram, which means potassium and sodium ions can dope each other in the lattice after cooling from a high temperature liquid phase to a solid state . The KCl crystal doped with NaCl to form the defect center can be used as color center laser crystals.…”

Tunable interstitial anionic electrons in layered MXenes

“…Electrides are materials with interstitial anionic electrons (IAEs) occupying empty spaces, constituting the 'anions' in the system [1,2]. It is sometimes considered as defects if the density is very low, such as F-center, where unpaired electrons are bonded with vacancies, leading to the color change of the crystal [3,4]. When the intensity of the cavity electrons increases significantly and distributes uniformly, we can obtain the electrides and observe many intriguing properties, such as advanced light absorption ability [5,6], low work function [7,8], high electron mobility [9,10], and high carrier concentration [11,12], which can be applied in non-linear optical devices [13,14], electron emitter devices [15,16], high-speed electronic devices [17], superconductors [18,19], and chemical applications such as catalysis [20][21][22].…”