Laser-assisted resonance-energy transfer - art. no. 023812

The process of laser-assisted resonance-energy transfer (LARET) is describe d and analyzed within the framework of molecular quantum electrodynamics. L ARET is a higher-order perturbative contribution to the familiar spontaneou s dipole-dipole mechanism for resonance-energy transfer, in which an auxili ary laser field is applied specifically to stimulate the energy transfer. T he frequency of the auxiliary beam is chosen to be off-resonant with any mo lecular transition frequencies in order to eliminate direct photoabsorption by the interacting molecules. Here consideration is given to the general c ase where the energy exchange takes place between two uncorrelated molecula r species, as for example in a molecular fluid, or a system in which the mo lecules are randomly oriented. In the ensuing calculations it is necessary to implement phase-weighted averaging in tandem with standard isotropic ave raging procedures. Results are discussed in terms of a laser intensity-depe ndent mechanism for energy transfer. Identifying the applied field regime w here LARET should prove experimentally significant, transfer rate increases of up to 30% are predicted on reasonable estimates of the molecular parame ters. Possible detection techniques are discussed and analyzed with referen ce to illustrative models.