Deterministic coupling of delta-doped NV centers to a nanobeam photonic crystal cavity

TL;DR

This paper demonstrates a method for precisely positioning NV centers in diamond within nanobeam photonic crystal cavities, achieving high quality factors and enhanced emission, advancing quantum photonics applications.

Contribution

It introduces a delta-doping technique for deterministic placement of NV centers in photonic cavities with nanometer precision.

Findings

Cavities with Q up to ~24,000 and mode volume ~0.47(λ/n)^3.

Resonant enhancement of NV zero-phonon line with Purcell factor ~20.

First step towards deterministic NV-cavity coupling.

Abstract

The negatively-charged nitrogen vacancy center (NV) in diamond has generated significant interest as a platform for quantum information processing and sensing in the solid state. For most applications, high quality optical cavities are required to enhance the NV zero-phonon line (ZPL) emission. An outstanding challenge in maximizing the degree of NV-cavity coupling is the deterministic placement of NVs within the cavity. Here, we report photonic crystal nanobeam cavities coupled to NVs incorporated by a delta-doping technique that allows nanometer-scale vertical positioning of the emitters. We demonstrate cavities with Q up to ~24,000 and mode volume V ~ $0.47({\lambda}/n)^{3}$ as well as resonant enhancement of the ZPL of an NV ensemble with Purcell factor of ~20. Our fabrication technique provides a first step towards deterministic NV-cavity coupling using spatial control of the emitters.