Design for telecom-wavelength quantum emitters in silicon based on alkali-metal-saturated vacancy complexes

TL;DR

This paper proposes a design approach for silicon-based quantum emitters operating at telecom wavelengths, focusing on alkali-metal-saturated vacancy complexes, and predicts sodium variants of the Q center as promising candidates.

Contribution

It introduces a first-principles design methodology for telecom-wavelength quantum emitters in silicon, identifying sodium-doped Q centers as potential candidates.

Findings

Sodium-doped Q centers emit near telecom bands

Predicted ground state spin suitable for quantum applications

Design principles applicable to other defect complexes

Abstract

Defect emitters in silicon are promising contenders as building blocks of solid-state quantum repeaters and sensor networks. Here we investigate a family of possible isoelectronic emitter defect complexes from a design standpoint. We show that the identification of key physical effects on quantum defect state localization can guide the search for telecom wavelength emitters. We demonstrate this by performing first-principles calculations on the Q center, predicting its charged sodium variants possessing ideal emission wavelength near the lowest-loss telecom bands and ground state spin for possible spin-photon interface and nanoscale spin sensor applications yet to be explored in experiments.