Probing bianisotropic biomolecules via a surface plasmon resonance sensor

Area of Science:

• * Optoelectronics and Nanophotonics
• * Biophysics and Molecular Sensing

Background:

• * Surface Plasmon Resonance (SPR) sensors are crucial for label-free biosensing.
• * Detecting bianisotropic biomolecules requires specialized sensing mechanisms to account for their unique electromagnetic properties.

Purpose of the Study:

• * To develop and validate a transfer matrix method for probing bianisotropic biomolecules using SPR.
• * To investigate the influence of optical activity and bianisotropy on SPR sensor performance.

Main Methods:

• * Utilized a Kretschmann configuration SPR sensor with a graphene layer.
• * Employed wave vectors and 4x4 transfer matrices derived from anisotropic and magnetoelectric coupling constitutive relations.
• * Accounted for cross-polarization coupling through eigenstates and transverse field components.

Main Results:

• * Demonstrated enhancement of cross-polarized reflection waves near the SPR angle.
• * Showcased increased sensitivity when detecting bianisotropic biomolecules in aqueous solutions.
• * Validated the transfer matrix method's effectiveness through numerical simulations.

Conclusions:

• * The developed transfer matrix method accurately probes bianisotropic biomolecules.
• * This approach enriches SPR sensor theory for detecting chirality parameters.
• * Findings can guide the design of SPR sensors with improved sensitivity to chirality variations.