Variation of the Luminescence Lifetime of a Molecule near an Interface between Differently Polarizable Dielectrics

Abstract

IN a recent paper¹ the energy transfer from an excited molecule S to an acceptor A was considered as a retardation effect. In classical terms, the field of S induces A to oscillate and the induced field of A, arriving at S, slows down this oscillator. This effect may be studied, too, without A being an absorber, but simply a polarizable molecule, oscillating in phase with the radiation field of S at the location of A. Then the field which is produced by A and acting at S accelerates or slows down this oscillator depending on the phase relation to its motion; thus the decay time of the luminescence of S will be prolonged or shortened. This phase relation depends on the time needed for the propagation of the electromagnetic field from S to A and from A to S.