2019/11/11 by Samrat Roy, Arnab Mandal, Roy, Samrat +7
Engineering · Materials Science · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Nonlinear Optical Materials Research #Nonlinear Optical Materials Studies #Optics (physics.optics) #Perovskite Materials and Applications
paper · pdf · doi:10.48550/arxiv.1911.04147
openalex publication_date 2019/11/11 · openalex created_date 2019/11/22 · openalex updated_date 2026/07/28
We have investigated nonlinear refraction in all-inorganic halide perovskites, the CsPbBr3 and CsPbBr1.5I1.5 nanosheet and quantum dot colloids in toluene, by a novel beam deflection technique using near-resonant continuous wave lasers. The nonlinear refraction and its time-evolution measured here have originated from thermal lensing effect. Nonlinear behaviour of heat transport in terms of intensity dependent thermal diffusion rate has been observed. Effects of convective heat flow have been measured at high intensities. Quantum dots have higher nonlinear refraction as compared to the corresponding nanosheet samples, presumably due to reduced dimensionality. The effective values of nonlinear refractive index, estimated here for near-resonant excitations, exceed those reported in the literature for organic-inorganic hybrid perovskites in the nonresonant excitation regime, by several orders of magnitude.