Energy transfer between colloidal semiconductor nanocrystals in an optical microcavity

The authors have studied nonradiative energy transfer between semiconductor nanocrystals (NCs) placed in a Fabry-Pérot microcavity. The spectrally integrated fluorescence from a monolayer of single sized NCs in the cavity is enhanced by a factor of 4.8 compared to free space. For a monolayer of mixed sized NCs, the acceptor NC fluorescence intensity is enhanced by an additional factor of 2.7 due to energy transfer processes. When the cavity mode is resonant with the acceptor NC fluorescence emission maximum, donor NC emission is completely suppressed, providing a narrow spectral output.