Optics and Photonics Society of Iran

In this paper, a biosensor based on plasmonic grating (1D plasmonic crystal) has been investigated. The biological sample was the slice of the brain mouse. The field distribution has been visualized by Fourier Modal Method (FMM) which is suitable for periodic structures. In addition, the grating period has been swept from 150 nm to 950 nm in order to show the effect of period on the transmission. This sweep has been done for three different thicknesses (heights) of 150, 250, 300 and 450 nm. Full widths at Half Maxima (FWHM) for simulated graphs have been investigated and finally the height of 250 nm which offered 3 dips with narrow FWHM was selected. Among these three dips, the second dip with grating period of 595nm would have the most optimum sensing response.