Strain modulation of Si vacancy emission from SiC micro- and nanoparticles

TL;DR

This study demonstrates how strain in SiC nanoparticles can modulate the emission wavelength of Si vacancy defects, enabling tunable single-photon sources for quantum technologies.

Contribution

It reveals the relationship between strain and emission shifts in Si vacancy defects within SiC nanoparticles, providing a method to tune quantum emitters.

Findings

Emission shifts depend on defect location within particles.

Compressive strain of 2-3% causes measurable wavelength shifts.

Strain analysis correlates with emission wavelength changes.

Abstract

Single-photon emitting point defects in semiconductors have emerged as strong candidates for future quantum technology devices. In the present work, we exploit crystalline particles to investigate relevant defect localizations, emission shifting and waveguiding. Specifically, emission from 6H-SiC micro- and nanoparticles ranging from 100 nm to 5 $\mu$m in size is collected using cathodoluminescence (CL), and we monitor signals attributed to the Si vacancy (V$_{\textrm{Si}}$) as a function of its location. Clear shifts in the emission wavelength are found for emitters localized in the particle center and at the edges. By comparing spatial CL maps with strain analysis carried out in transmission electron microscopy, we attribute the emission shifts to compressive strain of 2-3% along the particle a-direction. Thus, embedding V$_{\textrm{Si}}$ qubit defects within SiC nanoparticles offers an interesting and versatile opportunity to tune single-photon emission energies, while simultaneously ensuring ease of addressability via a self-assembled SiC nanoparticle matrix.