Surface Plasmon Resonance Analysis of Cancer‐Related Refractive Index Variations Using a MoTe ₂ –Black Phosphorus–Cu Multilayer Structure

ABSTRACT Surface plasmon resonance (SPR) biosensors enable label‐free detection of cancer biomarkers. However, conventional noble‐metal‐based designs suffer from limited sensitivity and stability. In this work, a high‐performance multilayer SPR biosensor based on a MoTe 2 –black phosphorus–copper (MoTe 2 –BP–Cu) architecture is proposed for enhanced cancer‐related refractive index detection. The synergistic integration of Cu with two‐dimensional materials improves electromagnetic field confinement and plasmon–analyte interaction. The sensor performance is analyzed using the transfer matrix method (TMM) over physiologically relevant refractive index ranges. The optimized structure achieves a sensitivity of 350°/RIU and a figure of merit of 93, with a strong linear response enabling reliable discrimination of cancerous conditions. Machine learning validation using locally weighted linear regression (LWLR) further confirms predictive robustness. Compared to conventional SPR configurations, the proposed design demonstrates improved sensing performance and practical feasibility, highlighting its potential for early cancer screening and early detection, contributing to SDG 3 (good health and well‐being) through advanced point‐of‐care diagnostic technologies.