Abstract
We present an idea of grating-based plasmon biosensor utilizing phase detection to realize high resolution in finding a refractive index of a material put on the surface of a metal grating. Assuming the resolution in phase detection to be 2.5×10^<-2> degrees, we estimate the resolution of the biosensor as 7.5×10^<-7> refractive index units. We also discuss the possible improvement to realize a predicted superior limit of resolution around 10^<-8>.
