Second Order Nonlinear Optical Properties of the Single Crystal of N-Benzyl 2-methyl-4-nitroaniline: Anomalous Enhancement of the d₃₃₃ Component and Its Possible Origin

Abstract

A single crystal of N-benzyl 2-methyl-4-nitroaniline (BNA) whose dimensions were 8×10 mm (diameter × length) was grown using a vertical Bridgman method with sufficient optical transparency for spectroscopic use. Polarized reflection spectra of the crystal were measured in order to determine its linear optical parameters (refractive indices and extinction coefficients). The relative magnitudes of the d-tensor components of the crystal were determined to be d 333=(17±9)×d 322, d 322>d 311, d 311∼0 from polarization dependencies of the second harmonic generation. These results are in disagreement with previously reported theoretical studies, in which the effects of intermolecular interactions were completely neglected. Here, we have included these intermolecular interactions in the calculations assuming the presence of supra-molecular clusters. We conclude that the anomalous enhancement of d 333 is due to the interactions along the direction of the hydrogen bonds in the crystal and the resonance effect.

Coherent tunable monochromatic Terahertz-wave generation using N-Benzyl-2-methyl-4-nitroaniline (BNA) crystal

“…Figure 2 shows the refractive index of optical region with BNA crystal. Sellmeier equation of optical region [14] expressed by…”

Growth of N-benzyl-2-methyl-4-nitroaniline (BNA) single crystal fibers by micro-pulling down method

“…A monochromatic THz-wave sources [7][8][9][10] using a nonlinear optical (NLO) process were employed in developing of number of such applications, but the advancement of the broadband sources and the sources that possess some degree of frequency agility is desirable. Recently an ultra-broadband capability using difference-frequency generation (DFG) was demonstrated using organic crystals of 4-dimethylamino-N-methyl-4-stilbavolium tosylate (DAST) [11][12][13][14][15] and N-benzyl-2-methyl-4-nitroaniline (BNA) [16][17][18][19][20]. The tuning ranges of monochromatic THz-wave sources based on organic materials were much wider than those of inorganic materials.…”

First principal studies of spectroscopic (IR and Raman, UV–visible), molecular structure, linear and nonlinear optical properties of l-arginine p-nitrobenzoate monohydrate (LANB): A new non-centrosymmetric material

“…Organic materials show very good properties due to their fast and large nonlinear response over a broad frequency range, inherent synthetic flexibility, large optical damage threshold for laser power and low frequency dispersion systems. The main advantage of these materials is that their structure can be tailored to get the preferred NLO properties and can be used in terahertz (THz) generation as they posses low dielectric constants [1,[6][7][8][9]. L-arginine is well known organic material from amino acid family having good structural flexibility because it exists in zwitterionic form, has protonation of guanidyl, alpha amino group and deprotonation of carboxyl groups.…”