Nanotips for 0.5THz scattering scanning near field microscopy

TL;DR

This paper presents a comprehensive simulation-based approach for designing nanotips that enhance scattering efficiency and achieve high spatial resolution in 0.5THz near-field microscopy, enabling customized THz imaging solutions.

Contribution

It introduces a novel design method for nanotips tailored for 0.5THz s-SNOM, improving resolution and efficiency without relying on commercial AFM tips.

Findings

Achieves 40 nm spatial resolution at 0.5THz

Develops a full-wave simulation and dipole analysis model

Provides a customizable nanotip design approach

Abstract

This manuscript demonstrates the theory, design, and simulation of scattering scanning near field microscopy (s-SNOM) in 0.5THz. A comprehensive simulation model of nanotips' geometry, sample materials, and incident field is established to significantly improve the scattering efficiency and spatial resolution to achieve optimal performance. The theoretical model is based on full-wave simulation and dipole moment analysis which can describe the overall nanotip's geometry information to screen the optimal parameters corresponding to the 0.5THz, which is the center frequency of most THz sources. The customized nanotip can achieve 40 nm $(\lambda / 15000)$ spatial resolution while maintaining an excellent scattering efficiency. This nanotip design method doesn't depend on the homogenization commercial AFM tips, providing an approach for customized nanotip design of THz wave scattering near field microscopy.