Efficiency of Cathodoluminescence Emission by Nitrogen-Vacancy Color Centers in Nanodiamond

TL;DR

This study investigates how various factors influence cathodoluminescence emission from nitrogen-vacancy centers in nanodiamonds, demonstrating detectable CL in particles as small as 40 nm and highlighting key determinants of emission efficiency.

Contribution

The paper combines experiments and simulations to identify the relative importance of particle size, color center density, and energy conversion efficiency in CL emission from NV-doped nanodiamonds.

Findings

CL detectable in nanodiamonds as small as 40 nm

CL emission decreases significantly in smaller NDs

Energy deposition and conversion efficiency are key factors

Abstract

Correlated electron microscopy and cathodoluminescence (CL) imaging using functionalized nanoparticles is a promising nanoscale probe of biological structure and function. Nanodiamonds (NDs) that contain CL-emitting color centers are particularly well suited for such applications. The intensity of CL emission from NDs is determined by a combination of factors, including: particle size; density of color centers; efficiency of energy deposition by electrons passing through the particle; and conversion efficiency from deposited energy to CL emission. We report experiments and numerical simulations that investigate the relative importance of each of these factors in determining CL emission intensity from NDs containing nitrogen-vacancy (NV) color centers. In particular, we find that CL can be detected from NV-doped NDs with dimensions as small as ~ 40 nm, although CL emission decreases significantly for smaller NDs.