Anisotropic Generation and Detection of Surface Plasmon Polaritons Using Near-Field Apertured Probes

Most recent studies centered on light-matter interactions at the nanoscale rely on near-field microscopy. Despite this, few works have been reported to date regarding the anisotropic generation of surface plasmons polaritons on metallic surfaces. This phenomenon is attributed exclusively to scattering near-field probes. This work is dedicated to demonstrating that the anisotropic generation of surface plasmons polaritons is not exclusive to scattering probes. Using a near-field apertured probe, in collection mode, we demonstrate the generation and detection of such phenomenon. By analyzing the momentum components of the obtained near-field images, it is demonstrated that the detected signal is mostly composed of near-field components. Therefore, our approach reduces the contribution of propagating modes, consequently easing the interpretation of near-field images.