Details

Autor(en) / Beteiligte

• Nguyen, Dzung M
• Mayer, Thomas M
• Hubbard, Steven F
• Singer, Kenneth D
• Mann, J. Adin
• Lando, Jerome B

Titel

Polar Polymeric Langmuir−Blodgett Films for Optical Applications

Ist Teil von

• Macromolecules, 1997-10, Vol.30 (20), p.6150-6157

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

1997

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A side-chain liquid crystalline copolymer containing ether−nitrobiphenyl groups was investigated as a nonlinear optical material. Ultrathin films have shown second harmonic generation and therefore have a variety of interesting applications. Waveguides composed of multilayers of the copolymer have been fabricated, and propagation losses as low as 2.3 dB/cm in a lowest order TE mode at 800 nm wavelength have been measured. The second harmonic coefficient is d 33 = 42.0 ± 1.7 pm/V at the 1064 nm fundamental wavelength and is consistent with an oriented gas model. From spectroscopic ellipsometry measurements the film refractive index is 2.24 ± 0.15 and the extinction coefficient ≤0.05 in the visible range of wavelengths. The monolayer and multilayer repeat structures were also studied by X-ray reflectivity and diffraction. The optical thickness and the oscillations in the reflectivity were in reasonable accord with a repeat length of about 3.6 nm.