Low-temperature diamagnetic muonium states in n-type gallium arsenide

Zero-field depolarization rates and transverse-field mu SR precession signals are investigated for six n-type GaAs samples to obtain information on the low-temperature diamagnetic muonium state. The onset temperature for growth of the Mu(T)(-) component shifts downward with n-type concentration, as expected for e(-) capture. A zero-field feature depends on donor species and concentration, suggesting donor involvement in the low-temperature state, thus supporting assignment to a Mu-donor pair. (C) 2000 Elsevier Science B.V. All rights reserved.