ph6b00045_si_001.pdf (447.77 kB)
Coupling of Surface-Plasmon-Polariton-Hybridized Cavity Modes between Submicron Slits in a Thin Gold Film
journal contribution
posted on 2016-04-25, 00:00 authored by Roman Walther, Stefan Fritz, Erich Müller, Reinhard Schneider, Dagmar Gerthsen, Wilfried Sigle, Tsofar Maniv, Hagai Cohen, Christian Matyssek, Kurt BuschElectron energy loss
spectroscopy (EELS) in a monochromated transmission
electron microscope is applied to probe standing-wave-like cavity
modes hybridized with surface plasmon polaritons (SPP) in rectangular
submicron slits in a thin gold film. Coupling of hybridized SPP-cavity
modes between two adjacent slits is studied by systematically varying
the width of the metal bar d that separates the identical
slits in a two-slit system. Measurements on two-slit systems with
different slit lengths L and fixed width reveal energy
shifts and mode splitting of the fundamental SPP cavity mode which
can be generally described as a function of a dimensionless scaling
parameter L/d. Numerical simulations
with the Discontinuous Galerkin Time-Domain (DGTD) method confirm
the experimental data and reveal insights into the underlying complex
coupling mechanisms.