In this paper, the lateral beam shift in a prism-waveguide coupling system at wavelengths ranging from visible to near infrared is theoretically examined. A simple theoretical formula is derived to analyze the behavior of the beam shift. We demonstrate that large positive and negative lateral optical beam shifts can be obtained when guided modes are excited. It is also found that the magnitude of the beam shift is closely related to the intrinsic and radiative damping. When the intrinsic damping is larger than the radiative damping, negative lateral beam shift occurs. Numerical calculations confirm the theoretical analysis and show that a beam shift of the order of millimeters is possible.

The giant Goos-Hänchen shift on a long-range surface plasmon (LRSP) configuration is examined theoretically. This lateral shift at the resonance of the LRSP can be two orders of magnitude greater than a wavelength. The analytical formulas of the radiative damping and the intrinsic damping of the LRSP are derived. It is found that the thicknesses of the second medium and the metal film determine the radiative damping and the intrinsic damping is illuminated by the imaginary part of the dielectric constant of the metal. Negative lateral beam shift occurs when the intrinsic damping is larger than the radiative damping. The theoretical results show good agreement with the predictions of the formulas.

An oscillating wave sensor based on Fabry-Perot resonance modes has been developed. Different from the surface plasmon resonance sensors and the waveguide mode sensors in which the sample is located in the evanescent field region, the proposed device contains the sample in the core region that supports the oscillating field. Owing to the strong concentration of the electromagnetic field in the sensing medium, the proposed device exhibits unusual sensitivity enhancement, which has never been exploited in any other devices.

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