Optimized Kretschmann–Raether configuration for maximized electromagnetic near-field enhancement

This work focuses on maximizing the near-field enhancement effect of a Kretschmann–Raether configuration. Through theoretical calculation and numerical simulation, we demonstrate that a global optimization of excitation parameters provides 36 times more near-field intensity enhancement. This maximum near-field enhancement at the transmitted side of a metal surface occurs at the coalescence of the transmission coefficient’s pole and the reflection coefficient’s zero. The additional enhancement is possible by tuning the excitation wavelength, incident angle, and metal layer thickness synergistically. This work paves the way for further enhancing light-matter interaction in a broad application using layered structures.