Optical bistability in fluorescein dyes
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Optical bistability has been observed in highly concentrated fluorescein dye solutions and in thin (≈1 μm) doped polymeric films. At concentrations larger than 10−5 mole/l dye dimers are formed. For fluorescein dye, the dimer-monomer equilibrium constant is 105 l/mole so that most of the dye species are in the dimer form. At 480 nm the dimer absorption cross section is 10−18 cm2/molecule, while that for the dye monomer molecule is 7.6×10−17 cm2/molecule. Upon laser excitation dimers dissociate to form monomers thus providing a highly nonlinear laser induced absorption. This high nonlinear absorption coefficient can be utilized for optically bistable response of the dye system.
Optical bistability was observed by placing dye solutions or dye thin films inside a Fabry-Perot resonator and exciting it with 480 nm dye laser pulses of 10 ns duration. The effect is more pronounced in 10−4 mole/l fluorescein than in 10−6 mole/l fluorescein in which dimer formation is not that efficient.
In disodium fluorescein no significant dimer formation is observed even at 10−3 mole/l dye concentration. The observed bistability both in solution and in thin films can be explained in terms of recent models for optical bistability in nonlinearly absorbing molecular systems.
PACS33 42.65 42.70
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- 1.J.A. Goldstone Optical bistability InLaser Handbook, Vol. 4 M.L. Stitch, M. Bass (eds.) (North-Holland, Amsterdam 1985)Google Scholar
- 2.H.M. Gibbs:Optical Bistability: Controlling Light with Light (Academic, New York 1985)Google Scholar
- 3.A.R. Tanguay, Jr.: Opt. Eng.24, 2 (1985)Google Scholar
- 4.D.J. Williams (ed.): Nonlinear Optical Properties of Organic Molecules and Polymeric Materials., ACS Symposium Series 233, ACS, Washington, D.C., 1983Google Scholar
- 5.D.S. Chemla, J. Zyss:Nonlinear Optical Properties of Organic Molecules and Crystals, Vols. 1 and 2 (Academic, New York (1987)Google Scholar
- 6.T. todorov, L. Nikolova, N. Tumova, V. Dragotinova: Opt. Electron.13, 209 (1981); IEEE J. QE-22, 1262, (1986)Google Scholar
- 7.M.A. Kramer, W.R. Tompkin, R.W. Boyd: Phys. Rev. A34, 2026 (1986)Google Scholar
- 8.M. Orenstein, S. Speiser, J. Katriel: Opt. Commun.48, 367 (1984)Google Scholar
- 9.M. Orenstein, S. Speiser, J. Katriel: IEEE J. QE-21, 1513 (1985)Google Scholar
- 10.M. Orenstein, J. Katriel, S. Speiser: Phys. Rev. A35, 1192 (1987)Google Scholar
- 11.M. Orenstein, J. Katriel S. Speiser: Phys. Rev. A35, 2175 (1987)Google Scholar
- 12.R.W. Chambers, T. Kajiwara, D.R. Kearns: J. Phys. Chem.78, 380 (1974)Google Scholar
- 13.I. Lopez Arbeloa: Part 1, J. Chem. Soc., Faraday Trans. 277, 1725; Part 2. J. Chem. Soc., Faraday Trans. 2 77, 1735 (1981)Google Scholar
- 14.W.E. Ford: J. Photochem37, 189 (1987)Google Scholar
- 15.S. Speiser, N. Shakkour.: Appl. Phys. B38, 191 (1985) and references thereinGoogle Scholar
- 16.Step (5b) may actually involve excitation to S1 of A2 followed by rapid dissociation, which is kinetically the same, see for example: S. Speiser, V.H. Houlding, J.T.Yardley: Nonlinear optical properties of organic dye monomer-dimer-systems (to be published in Appl. Phys. B)Google Scholar
- 17.C.J.G. Kirkby, R. Cush, I. Bennion: Opt. Commun.56, 288 (1985)Google Scholar
- 18.Z.F. Zhu, E.M. Garmire: IEEE J. QE-19, 1495 (1983)Google Scholar
- 19.M.C. Rushford, H.M. Gibbs, J.L. Jewell, N. Peyghambarian, D.A. Weinberger, C.F. Li:Optical Bistability 2, ed. by C.M. Bowden, S.L. McCall Plenum, New York (1983) pp. 345–352Google Scholar
- 20.D.A.B. Miller: J. Opt. Soc. Am. B1, 857 (1984)Google Scholar