Hyperfine clock transitions of bismuth donors in silicon detected by spin-dependent recombination

Abstract

Bismuth donors ion-implanted in ${}^{28}\mathrm{Si}$ and ${}^{\text{nat}}\mathrm{Si}$ are studied using magnetic resonance spectroscopy based on spin-dependent recombination. The hyperfine clock transition, at which the linewidth is significantly narrowed, is observed for the bismuth donors. The experimental results are modeled quantitatively by molecular orbital theory for a coupled pair consisting of a bismuth donor and a spin-dependent recombination readout center, including the effect of hyperfine and Zeeman interactions.