Optical bistability in a system of molecular J-aggregates and gold nanoparticles

Resumo

This paper considers a thin plane nanosystem consisting of molecular chains of dye J-aggregates forming bundles elongated in one direction and spherical gold nanoparticles located near them. Expressions are derived for the polarization of the exciton transition in the external field under the mutual influence of the dipole fields of the monomers constituting the dye J-aggregates and for the induced dipole of the nanoparticle. It is shown that in this system, mirrorless optical bistability of the fluorescence spectral density of the dye J-aggregates is possible, depending on the pump field intensity. The parameters of this dependence are critically determined by the distance between the molecular bundles and nanoparticles and by the angle between the field polarization direction and the axis of the bundle of J-aggregates. The use of the nanosystem as a sensor is discussed.