Prism-based Kretschmann configuration SPR systems require polarizer for P-polarized light for exciting surface plasmons at the metal-dielectric surface while fiber-optics based SPR configuration does not require polarizer, why?
Only p-polarized light will excite surface plasmons, regardless of the instrument configuration. If you could cite specifics of the fiber-optic instrument design you're referring to, it might clarify the problem and help reach a solution.
In both cases some amount of light with right polarisation is needed. In case of prism configuration unnecessary polarisation is just filtered out to get better sensitivity. This is simple and efficient. With fiber optics maintaining right polarisation is quite tricky, it is easier to live with some baseline, especially when measurements are spectroscopic in principle.
Basically, one can do prism configuration without polariser and/or fiber-optic configuration with polariser. It is possible, but in many cases not reasonable.
Thank you Dr Nelson and Dr Nizamov. But very recently two research groups have reported smartphone based surface plasmon resonance(SPR) platform integrating with optical fibers. They have not used any polarizer. I am attaching herewith their papers.
What you mean by "but"? There is no contradiction here. The natural light is a mixture of all possible linear polarisation states and can be represented as a sum of p- and s- polarised light. The part of light with right polarisation (p-) undergoes SPR, the other part (s-) is simply reflected in conditions of TIR, giving a baseline of approximately 0.5 (see Fig.2 in OSA). Using polariser one can filter out unnecessary s-polarisation and remove that baseline - this is what is normally done in prism configuration. But polarisation maintaining fiber-optics is very tricky and not always possible. It is easier to measure the spectrum and subtract the baseline. It is a conventional principle of fiber-optic SPR for over decade.
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