We excited multiple surface-plasmon-polariton (SPP) waves guided by the interface of a metal and a chiral sculptured
thin film (STF). Chiral STFs made by thermally evaporating NaF and either 3, 4, or 5 periods in thickness were
deposited on a metal film by oblique angle deposition accompanied by substrate rotation, each period being 300 nm, for plasmonic investigations in the Turbadar-Kretschmann-Raether (TKR) configuration. Reflectances were measured for a range of incidence angles for both p- and s-polarization states of the incident monochromatic light. Several reflectance minimums independent of the thickness of the chiral STF were obtained, indicating that multiple SPP waves had been excited.
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