Molecular Plasmon-Phonon Coupling.
Charged polycyclic aromatic hydrocarbons (PAHs), ultrasmall analogs of hydrogen-terminated graphene consisting of only a few fused aromatic carbon rings, have been shown to possess molecular plasmon resonances in the visible region of the spectrum. Unlike larger nanostructures, the PAH absorption spectra reveal rich, highly structured spectral features due to the coupling of the molecular plasmons with the vibrations of the molecule. Here, we examine this molecular plasmon-phonon interaction using a quantum mechanical approach based on the Franck-Condon approximation. We show that an independent boson model can be used to describe the complex features of the PAH absorption spectra, yielding an analytical and semiquantitative description of their spectral features. This investigation provides an initial insight into the coupling of fundamental excitations-plasmons and phonons-in molecules.
Department of Chemistry, Rice University , Houston, Texas 77005, United States.|Laboratory for Nanophotonics, Rice University , Houston, Texas 77005, United States.
Yao
Y
Cui
Department of Electrical and Computer Engineering, Rice University , Houston, Texas 77005, United States.|Laboratory for Nanophotonics, Rice University , Houston, Texas 77005, United States.
Adam
A
Lauchner
Department of Physics and Astronomy, University of New Mexico , Albuquerque, New Mexico 87131, United States.
Alejandro
A
Manjavacas
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology , 08860 Castelldefels (Barcelona), Spain.|ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, 08010 Barcelona, Spain.
F Javier
FJ
Garcı A de Abajo
Department of Chemistry, Rice University , Houston, Texas 77005, United States.|Department of Electrical and Computer Engineering, Rice University , Houston, Texas 77005, United States.|Department of Physics and Astronomy, Rice University , Houston, Texas 77005, United States.|Laboratory for Nanophotonics, Rice University , Houston, Texas 77005, United States.
Naomi J
NJ
Halas
Department of Electrical and Computer Engineering, Rice University , Houston, Texas 77005, United States.|Department of Physics and Astronomy, Rice University , Houston, Texas 77005, United States.|Laboratory for Nanophotonics, Rice University , Houston, Texas 77005, United States.
Peter
P
Nordlander
PAHs; graphene; plasmonics; plasmon−phonon coupling; polyacenes