Resolution and sensitivity in surface plasmon microscopy and sensing

The use of surface plasmons on planar surfaces for the characterisation of those surfaces is analysed. In particular, analytic expressions are derived for the sensitivity of such characterisation to the variation of bulk refractive indices, and to the addition of thin dielectric layers on the plasmon supporting surface. Comparison between surface plasmon and dielectric waveguide techniques is made. Surface plasmon microscopy is then considered, and relationships between sensitivity and resolution are derived. The interaction of plasmons with surface features is considered, and the effects in imaging of step and periodic features are specifically analysed. Other aspects relating to implementation and possible improvements to the technique are discussed.