3H-1 Sensitivity of Surface Plasmon Resonance Sensors for the Measurement of Acoustic Transients in Liquids

Surface plasmon resonance (SPR) excited optically via attenuated total internal reflection (ATR) represents a broadband sensing principle for acoustic pulse detection. The reflectivity and phase of a p-polarized laser beam incident on a thin metal film under SPR conditions are strongly dependent on ambient conditions that are changed by an acoustic wave. Depending on the order of layers, SPR sensors can be arranged in the Kretschmann or in the Otto configuration. The aim of this study was to compare both configurations and to find the most sensitive conditions for phase and reflectivity sensitive sensors. To find out the positions of maximum sensitivity theoretically, numerical calculations were carried out varying the layer dimensions and the angle of incidence