Two-Photon Photochromism of an Organic Material for Holographic Recording

• Published in: Chemistry of materials Vol. 14; no. 9; pp. 3663 - 3667
• Main Authors: Belfield, Kevin D, Liu, Yong, Negres, Raluca A, Fan, Meigong, Pan, Guilan, Hagan, David J, Hernandez, Florencio E
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.09.2002
• Subjects: Chemistry; Exact sciences and technology; Fundamental areas of phenomenology (including applications); General and physical chemistry; Holographic recording materials; optical storage media; Optical materials; Optics; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Physics; Polymers and organics; Two photon process; Photochromism; Nitrogen heterocycle; Isomerization; Furan derivatives; Holography; Photochemical reaction; Experimental study; Oxygen heterocycle; Transmittance; Absorption spectrum; Ultraviolet irradiation; Optical material; Recording material; Indole derivatives; Organic compounds
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm0107981

We report the two-photon-induced photoisomerization of 3-[1-(1,2-dimethyl-1H-indol-3-yl)-ethylidene]-4-isopropylidene-dihydrofuran-2,5-dione (1), a photochromic compound with λmax = 385 nm, using 775-nm femtosecond pulsed laser irradiation. The resulting photoisomer had λmax = 582 nm. The kinetic rate constant for the two-photon-induced electrocyclic isomerization reaction was measured at two different intensities (two different powers), showing a quadratic dependence with respect to the pump intensity. Results of pump−probe solution phase experiments and guest/host polymer thin film interferometric imaging studies are reported. A two-photon absorption molecular cross section σ2 = 10.3 × 10-48 cm4·s/photon was measured using Z-scan, further supporting a two-photon-induced isomerization process. Two-photon-induced interferometric recording in a fulgide-containing polymer film was demonstrated.