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arXiv · 2601.07188

Improvement of a focused ion beam fabricated diamond pillar for scanning ensemble nitrogen-vacancy magnetometry probe using an ultrapure diamond

Dwi Prananto·Yifei Wang·Yuta Kainuma·Kunitaka Hayashi·Masahiko Tomitori·Toshu An
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Abstract

Scanning diamond nitrogen-vacancy probe microscopy (SNVM) is an important tool for studying nanoscale condensed-matter phenomena. Ga$^+$-ion-focused-ion-beam (FIB) milling has been introduced as a method for fabricating SNVM, while the probe diameter is limited to a few micrometers due to Ga$^+$-induced damage. We report a method for improving the quality of FIB-fabricated SNVM probes by polyvinyl alcohol and Pt/Pd capping, followed by post-fabrication UV/ozone exposure. The effectiveness of the method is confirmed by the fabrication of an 800 nm-diameter probe with shallow NV centers, demonstrating an imaging of maze-like magnetic domain structure with a resolution of a few hundred nanometers and an improved sensitivity of 6.7 $\mu$T/Hz${1/2}$, while preserving spin coherence properties.

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Dwi Prananto, Yifei Wang, Yuta Kainuma, Kunitaka Hayashi, Masahiko Tomitori, Toshu An. 2026-01-12. Improvement of a focused ion beam fabricated diamond pillar for scanning ensemble nitrogen-vacancy magnetometry probe using an ultrapure diamond. https://doi.org/10.35848/1347-4065%2Fae7f5f

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