        Finite difference time-domain (FDTD)    !"  !" #$% % &  ’  "!() !* +  !"" &  ,*  ’ -.  +  /   . &  )  12  34 & 5  ’  !" #$%  162 " "( 7) 162 ,  " & %! 8!9 / . " & :   12  & 5 ; 13.5  ?*  %!*   !" #$%  @ !* +    8(A !* ,*   B" " /(     . C 6+ 162 ’ " "( !""   162 & ) !() & ! D.  !" #$%  )  &       + PACS 040.0040 050.005 Analysis of Plasmonic-Based MSM Photodetector with Optimized Parameters Fadakar Masouleh, Farzaneh 1 ; Mashayekhi, Hamidreza 1 ; Das, Narottam 2 1 Physics Group, University of Guilan, Rasht, Iran Department of Electrical and Computer Engineering, Curtin University, Perth, WA 6845, Australia 2 E-mail: fafadakar@msc.guilan.ac.ir, mashhr@guilan.ac.ir, narottam.das@curtin.edu.au Abstract- Finite differenc time-domain (FDTD) method is used to simulate the light absorption in a novel plasmonic-based photodetector with nano-gratings. Slit width is one of the effective parameters for the light absorption enhancement in metal-semioconductor-metal photodetectors. FDTD simulation results show ~13.5-times light absorption enhancement according to the changes in duty cycle and number of nano-gratings on each side of the slit. Keywords: FDTD simulation, Light absorption, Nano-structured MSM-PDs, Surface plasmon polariton. PACS No: 040.0040, 050.0050            "2 G! +2 1 H(; I&B J 1 K*" L J 2 1 / N OB" &) K!6A B" P&12 N 2 G @) Q*+ OB" P"G  *!R+ 7 N S(& L’: fafadakar@msc.guilan.ac.ir, mashhr@guilan.ac.ir, narottam.das@curtin.edu.au