High-performance cancer detection using Weyl semimetal-based surface plasmon polaritons

Abstract This study investigates a novel biosensor configuration based on Weyl semimetals, utilizing mid-infrared surface plasmon polaritons (SPPs) for high-sensitivity cancer detection. Numerical simulations using the 2 × 2 transfer matrix method reveal a sharp resonance dip induced by the SPP mode. Electric field analysis confirms that the resonance dip is strongly enhanced at the Weyl semimetal/sensing medium interface, decaying exponentially into the medium. The sharp mode is identified as an SPP localized at the interface. The resonance angle exhibits a linear dependence on the refractive index of the sensing medium, significantly improving biosensor performance. The sensor demonstrates a sensitivity of 130 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>deg</mml:mi> <mml:mo>.</mml:mo> <mml:msup> <mml:mi>RIU</mml:mi> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> , a linearity of R 2 = 0.999, and a figure of merit (FOM) exceeding 2166 RIU −1 . This Weyl semimetal-based plasmonic configuration offers a highly sensitive approach for cancer cell detection in the mid-infrared range.