title: Two-photon absorption in two-dimensional conjugated quadrupolar chromophores.
abstract: We present ultrafast z-scan measurements of the two-photon absorption (TPA) spectra of a pair of two-dimensionally conjugated quadrupolar donor/acceptor (D/A) chromophores. The all-donor substituted species displays a peak TPA cross section [sigma(2)=520+/-30 GM] that is more than twice that of the D-A species [sigma(2)=240+/-20 GM]. Unlike previous structure-property studies that have evaluated TPA behavior for D/A molecules through the comparison of dipolar and quadrupolar compounds, both molecules investigated herein are quadrupolar, ultimately providing a more consistent evaluation of the effects of donor and/or acceptor substitution on the TPA of conjugated chromophores.
authors.affiliation: Department of Physics, University of Alberta, Edmonton, Canada.
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Slepkov
authors.forename: Frank A
authors.initials: FA
authors.lastname: Hegmann
authors.forename: Rik R
authors.initials: RR
authors.lastname: Tykwinski
authors.forename: Kenji
authors.initials: K
authors.lastname: Kamada
authors.forename: Koji
authors.initials: K
authors.lastname: Ohta
authors.forename: Jeremiah A
authors.initials: JA
authors.lastname: Marsden
authors.forename: Eric L
authors.initials: EL
authors.lastname: Spitler
authors.forename: Jeremie J
authors.initials: JJ
authors.lastname: Miller
authors.forename: Michael M
authors.initials: MM
authors.lastname: Haley