Modeling of radiative emission from shallow color centers in single crystalline diamond

TL;DR

This paper develops a framework to model how the radiative emission rates of shallow color centers in diamond are affected by their proximity to surfaces, considering crystal orientation and surface cut, aiding quantum technology applications.

Contribution

It introduces a comprehensive model for analyzing depth-dependent emission rates of shallow diamond color centers, accounting for crystal orientation and surface effects.

Findings

Radiative lifetime increases as emitters approach the surface.

Surface orientation significantly influences emission properties.

Model can be extended to various diamond defect types.

Abstract

Optically active defects in diamond are widely used as bright single-photon sources for quantum sensing, computing, and communication. For many applications, it is useful to place the emitter close to the diamond surface, where the radiative properties of the emitter are strongly modified by its dielectric environment. It is well-known that the radiative power from an electric dipole decreases as the emitter approaches an interface with a lower-index dielectric, leading to an increase in the radiative lifetime. For emitters in crystalline solids, modeling of this effect needs to take into account the crystal orientation and direction of the surface cut, which can greatly impact the emission characteristics. In this paper, we provide a framework for analyzing the emission rates of shallow (<100 nm) defects, in which optical transitions are derived from electric dipoles in a plane perpendicular to their spin axis. We present our calculations for the depth-dependent radiative lifetime for color centers in (100)-, (110)-, and (111)-cut diamond, which can be extended to other vacancy defects in diamond.