The reflected back focal plane from a microscope objective is known to provide excellent information of material properties and can be used to analyze the generation of surface plasmons and surface waves in a localized region. Most analysis has concentrated on direct measurement of the reflected intensity in the back focal plane. By accessing the phase information, we show that examination in the back focal plane becomes considerably more powerful allowing the reconstructed field to be filtered, propagated and analyzed in different domains.
View Article and Find Full Text PDFThe localized properties of surface plasmons (SPs) and surface waves can be measured with a modified confocal microscope. An interference signal arises from a locally generated reference close to normal incidence and the beam that forms the surface wave. A spatial light modulator can impose different phase shifts on the part of the incident light to recover the properties of the SP.
View Article and Find Full Text PDFIn this paper, we present a direct method to measure surface wave attenuation arising from both ohmic and coupling losses using our recently developed phase spatial light modulator (phase-SLM) based confocal surface plasmon microscope. The measurement is carried out in the far-field using a phase-SLM to impose an artificial surface wave phase profile in the back focal plane (BFP) of a microscope objective. In other words, we effectively provide an artificially engineered backward surface wave by modulating the Goos Hänchen (GH) phase shift of the surface wave.
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