Enhancing Optical Readout from Diamond AFM Tips for Quantum Nanosensing

TL;DR

This paper demonstrates that diamond AFM tips with pyramid geometry significantly enhance the optical collection efficiency of silicon-vacancy centers, improving quantum nanosensing capabilities.

Contribution

The study shows that AFM diamond pyramid tips can channel photoluminescence efficiently, achieving up to 8 times higher collection, with experimental results supported by numerical simulations.

Findings

Enhanced PL collection up to 8 times

Efficient channeling of emitted light in DP geometry

Good agreement between experiments and FDTD simulations

Abstract

Color centers in diamond are promising candidates for quantum nanosensing applications. The efficient collection of the optical signal is the key to achieving high sensitivity and resolution, but it is limited by the collection optics. Embedding the color centers in diamond microstructures can help to enhance the collection efficiency, but often require challenging fabrication and integration. Here we investigate the photoluminescence (PL) of silicon-vacancy (SiV) centers in commercially available atomic force microscope (AFM) diamond pyramid (DP) tips. We find that the DP geometry efficiently channels PL emitted at the DP apex towards the base, where we experimentally demonstrate an enhanced PL collection of up to 8 times higher compared to other directions. Our experimental observations are in good agreement with numerical simulations using a finite-difference time-domain (FDTD) method. Our results indicate that AFM tips could be an economical, efficient and straightforward way of implementing color-center-based nanosensing as they provide enhanced sensitivity and easy integration with existing AFM platforms.