title: Mechanism of polarization-induced single-photon fluorescence enhancement.
abstract: The single-photon fluorescence (SPF) of IR125 can be enhanced when the laser polarization changes from linear through elliptical to circular [A. Nag and D. Goswami, J. Chem. Phys. 132, 154508 (2010)]. In this paper, we further explain and discuss the physical control mechanism. Our theoretical and experimental results demonstrate that the SPF enhancement can be attributed to the nonresonant two-photon absorption of a higher excited state. We conclude that the SPF intensity involving the nonresonant multiphoton absorption of the higher excited state can be controlled by varying the laser polarization.
authors.affiliation: State Key Laboratory of Precision Spectroscopy and Department of Physics, East China Normal University, Shanghai 200062, People's Republic of China.
authors.forename: Shian
authors.initials: S
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Chenhui
authors.initials: C
authors.lastname: Lu
authors.forename: Tianqing
authors.initials: T
authors.lastname: Jia
authors.forename: Zugeng
authors.initials: Z
authors.lastname: Wang
authors.forename: Zhenrong
authors.initials: Z
authors.lastname: Sun