An efficient fluorescent single-particle position tracking system for long-term pulsed measurements of nitrogen-vacancy centers in diamond

TL;DR

This paper presents a simple, real-time 3D position tracking system for nitrogen-vacancy centers in diamond, enabling high-resolution measurements in quantum sensing and biological applications using commercially available components.

Contribution

The authors develop a cost-effective, high-speed tracking system that operates without custom programming, allowing long-term pulsed measurements of NV centers with minimal position modulation.

Findings

Achieves position recovery within 0.9 seconds for 250 nm shifts

Supports tracking of low-photon-efficiency NV centers

Enables high-resolution magnetic resonance and Rabi oscillation measurements

Abstract

A simple and convenient design enables real-time three-dimensional position tracking of nitrogen-vacancy (NV) centers in diamond. The system consists entirely of commercially available components (a single photon counter, a high-speed digital-to-analog converter, a phase-sensitive detector-based feedback device, and a piezo stage), eliminating the need for custom programming or rigorous optimization processes. With a large input range of counters and trackers combined with the high sensitivity of single-photon counting, high-speed position tracking (upper bound recovery time of 0.9 s upon 250 nm of step-like positional shift) not only of bright ensembles but also of low-photon-collection-efficiency single to few NV centers is possible. The tracking requires position modulation of only 10 nm, which allows simultaneous position tracking and pulsed measurements in the long term. Therefore, this tracking system enables measuring a single spin magnetic resonance and Rabi oscillations at a very high resolution even without photon collection optimization. The system is widely applicable to various fields related to NV centers quantum manipulation research such as NV optical trapping, NV tracking in fluid dynamics, and biological sensing using NV centers inside a biological cell.