Optically induced dynamics of muonium centers in Si studied via their precession signatures

Abstract

We studied the influence of the optical excitation on three muonium centers ${\mathrm{Mu}}_{T}^{0}$, ${\mathrm{Mu}}_{\mathit{BC}}^{0}$, and ${\mathrm{Mu}}_{\mathit{BC}}^{+}$ in high resistivity silicon. These investigations were carried out on the spin precession signature of each center as a function of temperature. It is found that photoexcitation resulted in significant enhancements of the depolarization rates of the precession signals as the three muonium centers underwent interactions with photogenerated free carriers. The results are described by a three-state model involving transitions between ${\mathrm{Mu}}_{T}^{0}$, ${\mathrm{Mu}}_{\mathit{BC}}^{0}$, and ${\mathrm{Mu}}_{\mathit{BC}}^{+}$ as well as spin exchange processes.