Spectral dispersion of ultrafast optical limiting in Coumarin-120 by white-light continuum Z-scan

Abstract

Measurement of the wavelength dispersion of optical limiting in materials can provide invaluable information useful for laser safety device applications. However, it can be a tedious task when conventional tunable laser sources like the optical parametric amplifier are employed for excitation. Here we report the spectral dispersion of ultrafast optical limiting in the laser dye Coumarin-120 in the wavelength region 630 to 900 nm, measured in a single Z-scan, using the white-light continuum as the excitation source. Optical limiting is found to arise from two-photon absorption, and its spectrum agrees very well in shape with the linear absorption spectrum.

A novel zinc tetraphenylporphyrinate substituted in the axial position with one E-stilbazole: Synthesis, structure, and nonlinear optics

“…However, the surveys on the third order nonlinear optical properties of zinc tetraphenylporphyrinate substituted in the axial position with E-stilbazole are still limited [8]. Herein, a novel zinc porphyrin complex, namely, (5,10,15,[(E)-7-(diethylamino)-3-(2-(pyridin-4-yl)vinyl)-2H-chromen-2-one] zinc(II) (ZnTPPL) was prepared and structurally characterized by single crystal X-ray diffraction. Furthermore, the nonlinear optical and fluorescence properties of ZnTPPL were also investigated.…”

“…Porphyrinate zinc(II) complex (ZnTPPL) was prepared by reaction of ZnTPP with the appropriate E-stilbazole (L) in CHCl 3 . In this study, coumarin unit was introduced in the donor-acceptor type axial ligand due to the fact that it has been used as gain medium in some dye laser, and also plays an important role in electrophotographic and electroluminescent devices [9,10].…”

Dispersive white light continuum single Z-scan for rapid determination of degenerate two-photon absorption spectra

“…Although, the measured Z-scans show the nonlinear transmittance for different wavelengths they comprise both degenerate and nondegenerate 2PA over the entire spectrum of the WLC with unknown contribution of each process. Therefore, it is not feasible to determine the pure degenerate 2PA spectra using this method [25][26][27]. However, this method delivers a simple way to obtain the wavelength-resolved nondegenerate 2PA cross section.…”

ABCD Matrix formalism to Determine Nonlinear Refraction Coefficient by Z-Scan Technique

“…This is reflected in the X-scores and F-scores (Tables 4 and 5). The NUS + NTU cluster is four times more effective than the IISc + 7IITs cluster at the level of the second-order indicators 10,11 . Finally, we can give a broad estimate for the balance (evenness or consistency) as measured by  = F/X in the two clusters arranged into the boarder REF categories, as shown in Table 6.…”

“…The present work attempts to use the ABCD matrix formulation to describe the Z-scan technique to determine the nonlinear response of a material. There are several methods to measure nonlinear refraction including nonlinear interferometry 3,4 , degenerate four-wave mixing 5 , degenerate three-wave mixing 6 , ellipse rotation 7 , and beam distortion measurements 8 and Zscan 9,10 . The first three methods are potentially sensitive techniques, but these require relatively complex experimental apparatus, whereas Z-scan is a simple technique to study nonlinear refraction and nonlinear absorption.…”