# Nanodiamond arrays on glass for quantification and fluorescence characterisation

## TL;DR

This paper presents a precise method for creating nanodiamond arrays on glass to statistically analyze their fluorescence properties, advancing the development of quantum and sensing devices.

## Contribution

The study introduces a novel electron beam lithography-based technique for depositing nanodiamonds in predefined arrays for fluorescence characterization.

## Key findings

- Achieved 90% deposition yield across thousands of array sites
- Observed broad distribution of fluorescent lifetimes consistent with literature
- Demonstrated potential for hybrid photonic device fabrication

## Abstract

Quantifying the variation in emission properties of fluorescent nanodiamonds is important for developing their wide-ranging applicability. Directed self-assembly techniques show promise for positioning nanodiamonds precisely enabling such quantification. Here we show an approach for depositing nanodiamonds in pre-determined arrays which are used to gather statistical information about fluorescent lifetimes. The arrays were created via a layer of photoresist patterned with grids of apertures using electron beam lithography and then drop-cast with nanodiamonds. Electron microscopy revealed a 90% average deposition yield across 3,376 populated array sites, with an average of 20 nanodiamonds per site. Confocal microscopy, optimised for nitrogen vacancy fluorescence collection, revealed a broad distribution of fluorescent lifetimes in agreement with literature. This method for statistically quantifying fluorescent nanoparticles provides a step towards fabrication of hybrid photonic devices for applications from quantum cryptography to sensing.