title: Exchange narrowing and exciton delocalization in disordered J aggregates: simulated peak shapes in the two dimensional spectra.
abstract: Delocalized excitons in elementary linear J aggregates of two-level molecules absorb a photon into the low-energy edge of an exciton band. Absorption of a second photon is blue-shifted as the lowest energy state is occupied. This setup of states leads to a double-peak feature in a set of two dimensional photon echo spectra for excitonic bands. The delocalization properties of excitons, thus, strongly affect the peak lineshapes and their relative amplitudes. Simulations of various two dimensional spectra of a linear J aggregate are presented and possible schemes to quantitatively characterize the peak profiles are suggested. This allows to relate observable peak lineshapes to the exciton delocalization.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Han
authors.forename: Houyu
authors.initials: H
authors.lastname: Zhang
authors.forename: Darius
authors.initials: D
authors.lastname: Abramavicius