Comparison of Sensitivity of the Refractometric Methods of Frustrated Total Internal Reflection and Surface Plasmon Resonance

In recent years, an optical method for studying a thin boundary layer of media based on the phenomenon of surface plasmon resonance has been widely used. One of the advantages of this method is the experimentally established high sensitivity. According to theoretical calculations, another similar optical method of investigation based on the phenomenon of frustrated total internal reflection is more sensitive. The comparison of sensitivities to the change of the refractive index of the thin boundary layer of the investigated medium is performed for the two indicated optical refractometric methods: surface plasmon resonance and frustrated total internal reflection. It is shown that under the same experimental conditions, both methods have similar sensitivities to changes of the refractive index of the thin boundary layer of the investigated medium, and therefore each of them is noteworthy when choosing a method of investigation in each specific case.