Laser-Induced Broadband White Emission of NdAlO3 Nanocrystals in Alcohols

Abstract

Laser-induced white emission (LIWE) is a phenomenon in which a broadband emission is generated through focused laser excitation and described in several different materials; however, the vast majority was explored only in vacuum or air. Herein, LIWE for NdAlO3 nanocrystals immersed in different alcohols is described. It was observed as an evolution of bubbles in the focused point of excitation, which was responsible for the intermittence of the white emission due to changes in the excitation beam going through the bubbles. LIWE, although intermittent, presents a similar behavior regarding the nonlinear dependence of the excitation power in every alcohol used; however, a clear increase in the threshold of the LIWE phenomenon was observed, which was closely related to the relative permittivity of the alcohol in which the sample was immersed. This may open up the possibility to explore LIWE in solvents by properly choosing the material, relative permittivity of the solvent, and appropriate excitation power.