title: Large first hyperpolarizabilities in push-pull polyenes by tuning of the bond length alternation and aromaticity.
abstract: Conjugated organic compounds with 3-phenyl-5-isoxazolone or N,N'-diethylthiobarbituric acid acceptors have large first molecular hyperpolarizabilities (beta) in comparison with compounds with 4-nitrophenyl acceptors. For example, julolidinyl-(CH=CH)(3)-CH=N,N'- diethylthiobarbituric acid, which has 12 atoms between the donor and acceptor, has a beta(0) of 911 x 10(-30) electrostatic units, whereas (CH(3))(2)NC(6)H(4),-(CH=CH)(4)-C(6)H(4)NO(2), with 16 atoms between its donor and acceptor, has a beta(0) of 133 x 10(-30) electrostatic units. The design strategies demonstrated here have resulted in chromophores that when incorporated into poled-polymer electrooptic modulators exhibited significant enhancements in electrooptic coefficients relative to polymers containing the commonly used dye Disperse Red-1. Poled polymer devices based on these or related chromophores may ultimately lead to high-speed electrooptic switching elements with low drive-power requirements, suitable for telecommunications applications.
authors.forename: S R
authors.initials: SR
authors.lastname: Marder
authors.forename: L T
authors.initials: LT
authors.lastname: Cheng
authors.forename: B G
authors.initials: BG
authors.lastname: Tiemann
authors.forename: A C
authors.initials: AC
authors.lastname: Friedli
authors.forename: M
authors.initials: M
authors.lastname: Blanchard-Desce
authors.forename: J W
authors.initials: JW
authors.lastname: Perry
authors.forename: J
authors.initials: J
authors.lastname: Skindhøj