Publication: Enhanced sensitivity of guided mode resonance sensor through super-mode excitation at near cut-off diffraction
No. of Pages/File Size
Optics and Laser Technology. Vol.132, (2020)
Hironmay Deb, Nantarat Srisuai, Romuald Jolivot, Chamras Promptmas, Waleed S. Mohammed, Sakookan Boonruang (2020). Enhanced sensitivity of guided mode resonance sensor through super-mode excitation at near cut-off diffraction. Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/57883.
Enhanced sensitivity of guided mode resonance sensor through super-mode excitation at near cut-off diffraction
© 2020 Elsevier Ltd This work theoretically and experimentally demonstrates sensitivity enhancement in dielectric guided mode resonance (GMR) sensor via controlling a super-mode resonance at nearly cut-off diffraction (or at Rayleigh wavelength.) A bulk refractive index sensitivity can reach the upper limit at the value linearly proportional to the grating's periodicity. Super-mode excitation in the multilayer configuration of the 2D GMR sensor (a high refractive index film coated on a low refractive index imprinted grating) is demonstrated. This concept is verified using numerical calculations: Rigorous Coupled Wave Analysis (RCWA) and Homogeneous Waveguide Approximation (HWA). Modal allocation for each resonance in the GMR structure is performed using the approximated four-layer waveguide. The measured super-mode resonance has shown sensitivity enhancement almost three folds of that of the traditional guide mode resonance. Also, this realization occurs in a broad dynamic range through optimization of the structure's parameters. This guarantees a usage in multiple sensing applications.