Terahertz generation and optical properties of N-benzyl-2-methyl-4-nitroaniline single crystals in 0.1-2.0 THz range for photonic applications

We report on the THz generation and optical characterizations such as index of refraction, absorption coefficients of indigenously grown, potentially NLO active N-benzyl-2-methyl-4-nitroaniline (BNA) single crystals grown from four different solvents such as N, N dimethylformamide (DMF), Methanol (MeOH), Acetonitrile (ACN) and ACN: DMF (1:1) in an intentionally selected frequency range of 0.1-2.0 THz at room temperature (RT). The DMF was identified to be a promising candidate as it facilitated reduction in the inclusions. The powder Second Harmonic Generation (SHG) measurements performed on BNA polycrystalline samples revealed that their efficiencies were about 8.4 and 2.3 times higher than KDP and Urea samples respectively. The absorption coefficients and refractive indices made in this technologically important THz range using the BNA crystals grown from selected solvents exhibited, interestingly, solvent dependency. (C) 2019 Elsevier B.V. All rights reserved.