Superradiance in molecular H aggregates.
Direct evidence of superradiance from an organic semiconductor (quaterthiophene) whose molecules are arranged in a H aggregate fashion, is reported. Time resolved photoluminescence measurements show a linear correlation between the radiative lifetime (tau(rad)) of the purely electronic exciton recombination and the inverse of the number (N(C)) of the coherently emitting dipoles, i.e., tau(rad) proportional, variant 1/N(C). These data support the recently developed theoretical models describing the optical properties of H aggregates of rodlike molecules with a nonvanishing component of the perpendicular molecular transition dipole moment.
Meinardi
F
F
INFM and Dipartimento di Scienza dei Materiali, Universitá di Milano-Bicocca, via Cozzi 53, I-20125 Milano, Italy. meinardi@mater.unimib.it
Cerminara
M
M
Sassella
A
A
Bonifacio
R
R
Tubino
R
R