Two-photon absorbance

In a two-photon absorption process the first photon takes the molecule from the initial state 1 to a virtual state V and the second takes it from V to 2. As in Raman spectroscopy, the state V is not an eigenstate of the molecule. The two photons absorbed may be of equal or unequal energies, as shown in Figures 9.27(b) and 9.27(c). It is possible that more than two photons may be absorbed in going from state 1 to 2. Figure 9.27(d) illustrates three-photon absorption. [Pg.371]

For two-photon memories, a number of media types and reading mechanisms have been used (165). Generally, media comprise two photon-absorbing chromophores dissolved within a soHd polymer matrix. Suitable reversible photochromic dyes are, for example, spiropyrans. Although photochromic materials often suffer from photobleaching, as well as from instability leading to self-erasure, new materials and host environments are under development (172). Bacteriorhodopsin (BR) also has been proposed as a two-photon memory material. [Pg.154]

Brinas RP, Troxler T, Hochstrasser RM, Vinogradov SA (2005) Phosphorescent oxygen sensor with dendritic protection and two-photon absorbing antenna. J Am Chem Soc 127 11851-11862... [Pg.143]

Ogawa K, Kobuke Y (2009) Design of two-photon absorbing materials for molecular optical memory and photodynamic therapy. Org Biomol Chem 7 2241-2246... [Pg.144]

Kannan R, He GS, Lin TC, Prasad PN, Vaia RA, Tan LS (2004) Toward highly active two-photon absorbing liquids. Synthesis and characterization of 1, 3, 5-triazine-based octupolar molecules. Chem Mater 16 185-194... [Pg.144]

Padilha LA, Webster S, Przhonska OV, Hu H, Peceli D, Ensley TR, Bondar MV, Gerasov AO, Kovtun YP, Shandura MP, Kachkovski AD, Hagan DJ, Van Stryland EW (2010) Efficient two-photon absorbing acceptor-7t-acceptor polymethine dyes. J Phys Chem A, Submitted... [Pg.145]

Ramakrishna G, Vamavski O, Kim J et al (2008) Quantum-sized gold clusters as efficient two-photon absorbers. J Am Chem Soc 130 5032-5033... [Pg.353]

Two-Photon Absorbing Materials and Two-Photon-Induced Chemistry 3... [Pg.3]

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