Near-Field Modification of Interference Components in Surface Plasmon Resonance

TL;DR

This paper demonstrates how a sharpened tip can modify the interference components of surface plasmon resonance in ATR setups, enabling energy redirection before dissipation, with implications for interaction-free measurements.

Contribution

It introduces a novel method of manipulating surface plasmon energy flow using a sharpened tip, providing new insights into plasmonic interference and measurement techniques.

Findings

Sharpened tips can redirect plasmon energy before heat dissipation.

Simulation results support the analogy with a Mach-Zehnder interferometer.

Potential applications in interaction-free measurement setups.

Abstract

In an attenuated total reflection (ATR) geometry, energy extracted from an incident light beam by surface plasmon polariton (SPP) creation is implicitly considered to dissipate as heat. However, we show that a sharpened tip interacting with the SPP evanescent field can redirect some of the energy before such dissipation occurs. This behavior is examined with simple computer simulations and an analogy is drawn between it and a modified Mach-Zehnder interferometer. We also discuss "interaction-free" measurements with our set-up.