Studies of the morphology and optical properties of nano erbium oxide embedded in PMMA matrix

•PMMA samples doped 4 wt% and 8 wt% of nano Er2O3 (PMMA/nEr2O3) films have been synthesized.•The structural properties of PMMA/nEr2O3 samples have been investigated by HRTEM and FTIR.•The linear and nonlinear optical properties of the PMMA/nEr2O3 samples have been studied and explained. Doping polymethyl methacrylate (PMMA) with nano earth metal-oxides can play a significant role for modern optical devices. Films of PMMA doped with nEr2O3 (PMMA/nEr2O3, 4 and 8 wt%) were prepared using the casting technique. The size distribution of nEr2O3 was investigated at the nanoscale level by using high-resolution transmission electron microscopy (HR-TEM), and was found to be mixture of spherical particles ranging from 44 to 48 nm. The structure of the PMMA/nEr2O3 films was investigated using Fourier infrared transmission specrtoscopy, FITR. The linear and calculated nonlinear optical properties absorption were also investigated. The optical band gap of our fabricated films decreased by 6% due to doping by nEr2O3 at 8 wt%. Moreover, the estimation of the spectral moments (M−1 and M−3), energy dispersion, static refractive index (n0), the third-order susceptibility (χ(3)), nonlinear refractive index (n2) and the infinite dielectric constant (Ɛ∞) indicated a significant enhancement with increasing the concentration of nEr2O3. The present results indicated that PMMA/nEr2O3 could be used in different nonlinear optical applications such as image sensing and light-emitting diodes.