Muonium in ultra-pure germanium

The spin precession signals of positive muons (μ+) implanted into Ge single crystals of ultra-high purity (electronically active impurity concentration ≲ 3.1011cm-3 containing between 1012cm-3 and 1017cm-3 Si have been investigated at temperatures ranging from 5K to 280K in magnetic fields of 0.3 mT to 27.5 mT applied perpendicular to the μ+ polarization. As in previous work, the spin procession of muons in diamagnetic environments [“μ+”] and of normal (“isotropic”) muonium [Mu = (μ+e-)] as well as of anomalous (“anisotropic”) muonium [Mu∗] were observed. The damping of the Mu signal increases drastically with increasing Si content. This indicates that the muonium diffuses rather rapidly through the Ge matrix and interacts with solute Si atoms.