The Comparative Third‐Order Nonlinearities of Titanium Carbide and Tungsten Carbide in the Visible Regain

Abstract

This study investigates the structure and properties of Titanium carbide (TiC) and Tungsten carbide (WC) nanoparticles. The X‐ray diffraction patterns confirm the presence of a hexagonal structure in WC nanoparticles and cubic structure in TiC nanoparticles. Transmission electron microscopy analysis reveals the particle sizes to be within the range of 30–50 nm. The bandgap of TiC and WC nanoparticles are 3.5 and 3.6 eV, respectively based on diffuse reflectance spectroscopy (DRS) along with Kubelka–Munk. Furthermore, the optical phonons and dielectric function of WC and TiC nanoparticles are investigated using the reflectance spectra along with the Kramers–Kronig (KK) method. Furthermore, the Z‐scan technique, employing a Nd:YAG laser operating at a wavelength of 532 nm, is utilized to assess the nonlinear optical (NLO) characteristics of WC and TiC nanoparticles. The open aperture Z‐scan measurements of WC nanoparticles indicate reverse saturable absorption (RSA) behavior and a positive nonlinear refraction (NLR) coefficient. On the other hand, TiC nanoparticles show RSA behavior with a negative NLR effect. The order of NLR, nonlinear absorption coefficient, and the susceptibility of TiC and WC are 10−8 cm2 W−1, 10−4 cm W−1, and 10−6 esu, respectively.