Third order nonlinear optical effects in a new chalcone derivative embedded in a polymer host

A new organic nonlinear optical (NLO) material from the chalcone family: (2E)-1-(3,4-dichlorophenyl)-3-[4-(methylsulfanyl)phenyl]prop-2-en-1-one (DPMS) is crystallised in DMF solution. The functional groups in DPMS are identified by FTIR spectra. The thermal stability is studied using TGA/DTA. The polymethylmethacrylate (PMMA) film doped with DPMS was prepared. Direct and indirect band gap energy of DPMS doped PMMA is determined using U. V. Visible spectra. The nonlinear absorption coefficient and optical power limiting of the film was studied using Z-scan technique. The film exhibits a self focussing effect at a wavelength of 532nm. The results of optical limiting studies, shows that the film possesses reverse saturable absorption due to excited state absorption. The nonlinear optical properties of DPMS have been retained in the presence of a polymer material.