Numerical Investigation of a Kretschmann-Type Surface Plasmon Resonance Waveguide Sensor

A Kretschmann-type surface plasmon resonance waveguide sensor is analyzed using the wide-angle beam- propagation method (BPM) with the complex Pade approximant and the finite-difference time-domain (FDTD) methods based on the recursive convolution (RC) and piecewise linear RC (PLRC) techniques. The wavelength responses of the sensor are calculated, and a detailed comparison of the numerical results is made. The BPM results are validated through a comparison with the FDTD results, in which the PLRC technique is required in terms of accuracy. The waveguide sensor shows a maximum absorption wavelength shift from 0.609 to 0.623 mum, as the refractive index of an analyte is increased from 1.330 to 1.334, which is comparable to the sensitivity of the conventional Kretschmann configuration.