Template-Assisted Self Assembly of Fluorescent Nanodiamonds for Scalable Quantum Technologies

TL;DR

This paper introduces a scalable, template-assisted self-assembly technique for precisely arranging nanodiamonds with NV centers, enabling statistical analysis of their properties for quantum technology applications.

Contribution

A novel, scalable method for ordered nanodiamond array formation that allows detailed statistical study of their quantum and optical properties.

Findings

NV center properties are uncorrelated with nanodiamond size.

Heterogeneity in nanoscale environment affects NV center behavior.

Method enables assembly over millimeter-scale areas.

Abstract

Milled nanodiamonds containing nitrogen-vacancy (NV) centers provide an excellent platform for sensing applications as they are optically robust, have nanoscale quantum sensitivity, and form colloidal dispersions which enable bottom-up assembly techniques for device integration. However, variations in their size, shape, and surface chemistry limit the ability to position individual nanodiamonds and statistically study properties that affect their optical and quantum characteristics. Here, we present a scalable strategy to form ordered arrays of nanodiamonds using capillary-driven, template-assisted self assembly. This method enables the precise spatial arrangement of isolated nanodiamonds with diameters below 50 nm across millimeter-scale areas. Measurements of over 200 assembled nanodiamonds yield a statistical understanding of their structural, optical, and quantum properties. The NV centers' spin and charge properties are uncorrelated with nanodiamond size, but rather are consistent with heterogeneity in their nanoscale environment. This flexible assembly method, together with improved understanding of the material, will enable the integration of nanodiamonds into future quantum photonic and electronic devices.