Novel behavior of bond-centered muonium in heavily doped n-type silicon:: Curie-like spin susceptibility and charge screening

Bond-centered muonium (Mu(BC)(0)) has been observed in very heavily doped n-type Si:P. It exhibits a Curie-like electronic spin susceptibility which leads to a giant negative shift in the muon spin precession frequency.;At high dopant levels, the Mu(BC)(0) hyperfine parameters, deduced from a model involving spin exchange with free carriers, are significantly reduced from those in intrinsic Si. This indicates that the spin density distribution for Mu(BC)(0) in metallic SI:P is altered significantly by charge screening effects, likely a general phenomenon for deep impurities in materials with high carrier concentrations.