کنفرانس مهندسی برق ایران

صفحه اصلی / سی و چهارمین کنفرانس بین المللی مهندسی برق

Plasmonic Absorber-Assisted SPR Sensor with Tunable Dual Resonances for Refractive Index Sensing Applications

نویسندگان :

Elham Derakhti¹ Mohammad Ghanavati² Mohammad Azim Karami³

1- دانشگاه علم و صنعت ایران 2- دانشگاه علم و صنعت ایران 3- دانشگاه علم و صنعت ایران

کلمات کلیدی :

Surface plasmon resonance،Refractive index sensor،Plasmonic absorber،Multi-resonance structure،Finite element method

چکیده :

In this paper, a surface plasmon resonance based refractive index sensor using a dual-resonance plasmonic absorber is simulated and analyzed. The proposed structure consists of a gold substrate, a silicon dioxide layer, and an array of metal disks (gold metal) with two different radii, which are covered by a liquid crystal layer. Simulations are performed using the finite element method in the wavelength range of 900–2000 nm. Results show that the structure has two distinct resonant modes at wavelengths of about 1514 and 1152 nm. By changing the refractive index of the surrounding medium in the range of 1.00 to 1.06, a linear shift of the resonant wavelength is observed for both modes. The obtained sensitivities are 160.71 and 60.71 nm per unit refractive index (RIU), respectively, and the index of merit values were calculated to be about 0.99 and 0.66 1/RIU, respectively. The favorable optical performance and high sensitivity of the proposed structure make it a suitable option for biological and chemical applications based on the detection of refractive index changes.