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Intermolecular energy transfer in the presence of dispersing and absorbing media

Ho Trung Dung·Ludwig Knöll·Dirk-Gunnar Welsch
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Abstract

By making use of the Green function concept of quantization of the electromagnetic field in Kramers--Kronig consistent media, a rigorous quantum mechanical derivation of the rate of intermolecular energy transfer in the presence of arbitrarily shaped, dispersing, and absorbing material bodies is given. Applications to bulk material, multi-slab planar structures, and microspheres are studied. It is shown that when the two molecules are near a planar interface, then surface-guided waves can strongly affect the energy transfer and essentially modify both the (F\"{o}rster) short-range $R^{-6}$ dependence of the transfer rate and the long-range $R^{-2}$ dependence, which are typically observed in free space. In particular, enhancement (inhibition) of energy transfer can be accompanied by inhibition (enhancement) of donor decay. Results for four- and five-layered planar structures are given and compared with experimental results. Finally, the energy transfer between two molecules located at diametrically opposite positions outside a microsphere is briefly discussed.

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Ho Trung Dung, Ludwig Knöll, Dirk-Gunnar Welsch. 2001-07-30. Intermolecular energy transfer in the presence of dispersing and absorbing media. https://doi.org/10.1103/physreva.65.043813

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