Open AccessNonlinear optical properties of 2,4,5-Trimethoxy-4ʹ-nitrochalcone: observation of two-photon-induced excited-state nonlinearities
Author(s) -
Bing Gu,
Wei Ji,
Xiaoqin Huang,
P. S. Patil,
S. M. Dharmaprakash
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.001126
Subject(s) - excited state , femtosecond , two photon absorption , hyperpolarizability , nonlinear optics , laser , absorption (acoustics) , excitation , atomic physics , optics , materials science , physics , nonlinear system , nonlinear optical , quantum mechanics
We report experimental investigations of optical nonlinearities and nonlinear dynamics in acetone solution of 2,4,5-Trimethoxy-4- nitrochalcone. By performing Z-scans with femtosecond laser pulses at low excitation intensity, two-photon absorption (2PA) and third-order nonlinear refraction are measured. As laser excitation intensity exceeds a critical value, however, the interplay between third- and fifth-order nonlinearities is observed. It is also confirmed that fifth-order processes mainly originate from 2PA-induced excited-state nonlinearities by conducting femtosecond time-resolved degenerate pump-probe measurements. All the nonlinear parameters are determined unambiguously in the near infrared region of the 2PA cross-section, second-order hyperpolarizability, excited-state absorption cross-section, excited-state refraction cross-section, lifetime of excited states induced by 2PA, and critical population of the excited states in 2,4,5-Trimethoxy-4-nitrochalcone molecule.