The electrodynamics of single molecule fluorescence
J. Enderlein
Institute of Physical and Theoretical Chemistry, Eberhard Karls University Tuebingen
15:30 - 16:30 Thursday 14 June 2007 KFU Hörsaal 05.01 The lecture presents an overview of the electrodynamics of single
fluorescing molecule and its electromagnetic interaction with
matter. After considering the absorption and emission of light by
an ideal electric dipole in vacuum, the interaction of such a
dipole with an inhomogeneous environment is studied. Two special
cases are treated in detail: (i) a molecule close to a flat
stratified medium, and (ii) a molecule within a metallic spherical
nanocavity. The physical consequences of the interaction between
fluorescing molecules with an inhomogeneous environment are
discussed, in particular (i) the increase of excitation efficiency
due to local enhancement of electric fields, and (ii) the change of
the excited state lifetime due to virtual photon tunneling and the
back-reaction of the emitted field onto the emitting molecule. It
is shown how changing the excited state lifetime alters the
photostability, quantum yield of fluorescence, and the
absorption/emission spectral properties. Besides being of interest
from a fundamental point of view, the knowlegde of these changes is
of great importance for many spectroscopic techniques.
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