Quenching of two-photon fluorescence and stimulated anti-Stokes emission in rhodamine solutions.
Two-photon fluorescence (TPF) has been excited in different solutions of rhodamine 6G and rhodamine B with single 30-psec pulses from a Nd:YAG laser at 1.06 microm. Up to incident intensities of 6 x 10(28)photons cm(-2) sec(-1) the TPF intensity showed a quadratic dependence on the photon flux. At higher photon fluxes the TPF intensity increased less than quadratically with the incident intensity. A possible mechanism, not considered previously, for this quenching is stimulated Raman scattering. It was observed that TPFquenching and stimulated anti-Stokes emission had thresholds in the same power range.
Eichler
H J
HJ
Langhans
D
D
Klein
U
U