Control of the energy transfer with the optical microcavity

We present the first experimental observation that dipole-dipole interaction can be strongly enhanced by placing the system in a microcavity. We have studied the excitation energy transfer in poly(phenyl-p-phenylene vinylene) (PPPV) doped with DCM molecules, placed within a Fabry-Perot resonator. As the spectral position of the cavity resonant mode in tuned across the DCM absorption profile, the transfer efficiency from PPPV to DCM changes dramatically as revealed by photoluminescence (PL) spectra. This behavior is clear evidence for the increase of the dipole-dipole interaction strength at the cavity resonances mediated by propagating modes emitted from the excited dipoles.