fa Comparison of Tapered Optical Fiber Sensors Based on Gold, Silver, Copper and Aluminum Nanoparticles تخصصی Special پژوهشي Research <span style="font-family:Calibri,sans-serif;"><span style="font-size:11.0pt;">Four tapered optical fiber sensors based on the localized surface plasmon resonance (LSPR) method with Au, Ag, Cu, and Al nanoparticles on the fiber waist area are simulated and investigated. The simulation method is a combination of the </span></span><span style="font-family:Times New Roman,serif;"><span style="font-size:11.0pt;">finite-difference time-domain (FDTD)</span></span><span style="font-family:Calibri,sans-serif;"><span style="font-size:11.0pt;"> and </span></span><span style="font-family:Times New Roman,serif;"><span style="font-size:11.0pt;">finite element method (FEM)</span></span><span style="font-family:Calibri,sans-serif;"><span style="font-size:11.0pt;">. The transmittance spectrum of the tapered optical fiber by variation of analyte refractive index is obtained for these four sensors and their amplitude and wavelength sensitivities are compared. It is shown that the Au sensor has the highest amplitude sensitivity of -4.5 per refractive index unit (1/RIU) and the Ag sensor has the highest wavelength sensitivity of 174.9 (nm/RIU) among these sensors. The results show that if the environmental conditions and the possibility of design for these sensors are provided, each sensor has its own advantages for diagnosing the diseases with the analyte refractive index range of </span></span><span style="font-family:Times New Roman,serif;"><span style="font-size:11.0pt;">1.333‑1.403</span></span><span style="font-family:Calibri,sans-serif;"><span style="font-size:11.0pt;">.</span></span> <strong>Four tapered optical fiber sensors based on the localized surface plasmon resonance (LSPR) method with Au, Ag, Cu, and Al nanoparticles on the fiber waist area are simulated and investigated. The simulation method is a combination of the finite-difference time-domain (FDTD) and finite element method (FEM). The transmittance spectrum of the tapered optical fiber by variation of analyte refractive index is obtained for these four sensors and their amplitude and wavelength sensitivities are compared. It is shown that the Au sensor has the highest amplitude sensitivity of -4.5 per refractive index unit (1/RIU) and the Ag sensor has the highest wavelength sensitivity of 174.9 (nm/RIU) among these sensors. The results show that if the environmental conditions and the possibility of design for these sensors are provided, each sensor has its own advantages for diagnosing the diseases with the analyte refractive index range of 1.333‑1.403.</strong> Sensor, Tapered Optical Fiber, Localized Surface Plasmon Resonance, Nanoparticles Sensor, Tapered Optical Fiber, Localized Surface Plasmon Resonance, Nanoparticles 13 15 http://opsi.ir/browse.php?a_code=A-10-1972-6&slc_lang=fa&sid=1 Parisa Borjikhani Parisa Borjikhani 10031947532846009964 10031947532846009964 No Center of Excellence in Electromagnetics, Optical Communication Laboratory, Faculty of Electrical Engineering, K. N. Toosi University of Technology, Tehran, Iran Center of Excellence in Electromagnetics, Optical Communication Laboratory, Faculty of Electrical Engineering, K. N. Toosi University of Technology, Tehran, Iran Mohammad Ismail Zibaii Mohammad Ismail Zibaii 10031947532846009965 10031947532846009965 Yes Laser & Plasma Research Institute, Shahid Beheshti University, Tehran, Iran. Laser & Plasma Research Institute, Shahid Beheshti University, Tehran, Iran. Nosrat Granpayeh Nosrat Granpayeh 10031947532846009966 10031947532846009966 No Center of Excellence in Electromagnetics, Optical Communication Laboratory, Faculty of Electrical Engineering, K. N. Toosi University of Technology, Tehran, Iran Center of Excellence in Electromagnetics, Optical Communication Laboratory, Faculty of Electrical Engineering, K. N. Toosi University of Technology, Tehran, Iran