Systematic analysis of nonlinear optical properties in pristine and rare-earth-doped Zn2V2O7 for low-power optical limiting applications

This study focuses on the optical limiting (OL) as well as, nonlinear optical (NLO), properties of pristine and rare-earth (RE) doped zinc pyrovanadate (Zn₂V₂O₇), were systematically investigated through the Z-scan method operated at 532 nm wavelength within the nanosecond domain. RE-doped Zn₂V₂O₇ nanoparticles, where RE = Nd, Er, and Eu, are prepared through the hydrothermal method, and their structural, morphological, and optical properties are studied in detail. The X-ray diffraction studies describe the structure information and surface morphology it exhibits as revealed by scanning electron microscopy. The molecular structures and chemical bonding have been confirmed using Raman spectroscopy and Fourier-transform infrared spectroscopy. The linear absorption studies revealed decreased band gap energy upon doping with RE elements. Nonlinear optical studies conducted using the open-aperture (OA) Z-scan method showed that all the samples exhibited reverse saturable absorption (RSA) behavior through a mechanism involving the simultaneous absorption of two photons. Contrary to the pristine Zn₂V₂O₇, the OL and NLO behavior of the RE-doped samples are strongly enhanced. Among the materials under study, Eu-doped Zn₂V₂O₇ revealed the highest nonlinear optical absorption with better optical limiting performance compared to Nd and Er doping. These findings indicate that Eu-doped Zn₂V₂O₇ can be considered as a material with potential applications in low-power optical limiting devices due to its enhanced optical limiting characteristics and effective nonlinear absorption.