Electron nuclear double resonance with donor-bound excitons in silicon

TL;DR

This paper demonstrates a novel optical detection method for electron and nuclear spins of phosphorus donors in silicon using Auger-electron-detected magnetic resonance, enabling broadband and less restrictive experimental conditions.

Contribution

It introduces a new AEDMR and ENDOR technique for phosphorus donors in silicon that relaxes previous experimental constraints and broadens applicability.

Findings

Successful AEDMR detection in natural silicon

Optically-assisted nuclear spin control demonstrated

Relaxed conditions for strain, purity, and temperature

Abstract

We present Auger-electron-detected magnetic resonance (AEDMR) experiments on phosphorus donors in silicon, where the selective optical generation of donor-bound excitons is used for the electrical detection of the electron spin state. Because of the long dephasing times of the electron spins in isotopically purified $^{28}$Si, weak microwave fields are sufficient, which allow to realize broadband AEDMR in a commercial ESR resonator. Implementing Auger-electron-detected ENDOR, we further demonstrate the optically-assisted control of the nuclear spin under conditions where the hyperfine splitting is not resolved in the optical spectrum. Compared to previous studies, this significantly relaxes the requirements on the sample and the experimental setup, e.g. with respect to strain, isotopic purity and temperature. We show AEDMR of phosphorus donors in silicon with natural isotope composition, and discuss the feasibility of ENDOR measurements also in this system.