Performance Analysis of Chirped Graded Photonic Crystal Resonator for Biosensing Applications

In this manuscript, a chirped graded photonic crystal (PhC) resonator structure is optimized for biosensing applications. The proposed structure comprises a bilayer PhC with an aqueous defect layer, where the thickness grading within the material is introduced, considering alpha (<inline-formula&...

Full description

Saved in:
Bibliographic Details
Main Authors: Jasmine Saini, Ajay Kumar, Amit Kumar Goyal
Format: Article
Language:English
Published: MDPI AG 2024-12-01
Series:Photonics
Subjects:
Online Access:https://www.mdpi.com/2304-6732/11/12/1173
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this manuscript, a chirped graded photonic crystal (PhC) resonator structure is optimized for biosensing applications. The proposed structure comprises a bilayer PhC with an aqueous defect layer, where the thickness grading within the material is introduced, considering alpha (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>) as a grading parameter. The device performance is analytically evaluated using the finite element method (FEM). The impact of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>, the resonator thickness, and the incidence angle on the device performance is analyzed. Further, the device’s ability to be used as a biosensor is evaluated, considering cholesterol as an analyte. The analytical results demonstrate an average sensitivity of 410 nm/RIU, a quality factor of 0.91 × <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mn>10</mn><mn>3</mn></msup></semantics></math></inline-formula>, and a figure of merit (FOM) of 2.47 × <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mn>10</mn><mn>2</mn></msup></semantics></math></inline-formula><inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>RIU</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>, showing 88.5% and 43% improvements in sensitivity and FOM compared to recently reported devices. The device’s superior sensing performance makes it suitable for medical and commercial applications, while the use of thickness grading addresses fabrication limitations, offering a robust framework for advanced photonic device design.
ISSN:2304-6732