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Journal of the Optical Society of America B

Journal of the Optical Society of America B


  • Vol. 16, Iss. 11 — Nov. 1, 1999
  • pp: 1921–1935

Nonlinear optical waveguide spectroscopy of a conjugated polymer: poly(p-phenylenevinylene)

K. Ueberhofen, A. Deutesfeld, K. Koynov, and C. Bubeck  »View Author Affiliations

JOSA B, Vol. 16, Issue 11, pp. 1921-1935 (1999)

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We have measured intensity-dependent prism coupling of poly(p-phenylenevinylene) thin films with picosecond laser pulses in the range 750–1600 nm. We developed a refined evaluation method that yields the signs and absolute values of the nonlinear refractive index n2 and the nonlinear absorption coefficient α2. Strong two-photon absorption levels were found at 2.8 and 3.1 eV. We observed a resonance at 1.3 eV that behaves as saturable absorption, and several additional resonances and sign changes of n2 at even lower photon energies. We demonstrate reversible refractive-index changes Δn=+0.002 at 910–950 nm on a picosecond time scale. Even larger Δn appear feasible.

© 1999 Optical Society of America

OCIS Codes
(130.0130) Integrated optics : Integrated optics
(130.2790) Integrated optics : Guided waves
(160.5470) Materials : Polymers
(190.4390) Nonlinear optics : Nonlinear optics, integrated optics
(190.4400) Nonlinear optics : Nonlinear optics, materials
(310.2790) Thin films : Guided waves

K. Ueberhofen, A. Deutesfeld, K. Koynov, and C. Bubeck, "Nonlinear optical waveguide spectroscopy of a conjugated polymer: poly(p-phenylenevinylene)," J. Opt. Soc. Am. B 16, 1921-1935 (1999)

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