Two-photon absorption in two-dimensional conjugated quadrupolar chromophores.
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.
Slepkov
Aaron D
AD
Department of Physics, University of Alberta, Edmonton, Canada.
Hegmann
Frank A
FA
Tykwinski
Rik R
RR
Kamada
Kenji
K
Ohta
Koji
K
Marsden
Jeremiah A
JA
Spitler
Eric L
EL
Miller
Jeremie J
JJ
Haley
Michael M
MM