RF-μSR study of muonium charge states and dynamics in Si

The radio frequencyμSR technique developed at TRIUMF was used to measure the temperature dependence of the diamagnetic muon, Mu, and Mu* amplitudes in silicon between 10 K and 500 K. Six samples doped with phosphorus (n-type) and boron (p-type) in the concentration range 1011 to 1015 cm−3 were studied. In pure Si a very good fit over the whole temperature range is obtained from a model that includes the ionization of Mu* and Mu to a bond centeredμ+ followed at high temperature by charge exchange involving Mu.