Photoinduced charge carriers' accumulation and its impact on random lasing in Nd3+ doped (Pb, La)(Zr, Ti)O-3 ceramics

摘要

To pinpoint the driving forces behind the random lasing in Nd3+ doped lanthanum lead zirconate titanate (Nd: PLZT) ceramic plates, a combinatorial cavity with two gain media (Nd: YVO4 and Nd: PLZT) was used to study the switching feature between conventional lasing and random lasing oscillations. The complex laser output dynamics observed hinted that the photo-induced charge accumulation on the plate surface and the grain boundaries of Nd: PLZT is responsible for the lasing action switching, which was confirmed by a series of experiments, including strong electro-induced scattering, remarkable photoinduced currents, and light transmission reduction, along with measured single-pass-gain over the theoretical limit. It was found that the charge accumulation results in optical energy storage and nonuniform refractive index and hence strong scattering, which give rise to the random walks and weak localization of photons and long lasting lasing action and mode switching. Published by AIP Publishing.