Study of muonium behavior in n-type silicon for generation of ultra cold muonium in vacuum

Abstract Ultracold muonium (UCMu) is an important muonium (Mu) source for the generation of ultraslow muon beam for nanotechnological applications and for understanding hydrogen dynamics in materials. This study attempts to discover a new material for the generation of UCMu in vacuum. Muon spin rotation and relaxation measurements for n-type silicon (Si) between 7 K and 300 K were performed. The Mu rotation signal was evident at temperatures less than 200 K, indicating its presence. Moreover, the variation in relaxation rates of Mu formed deep inside and near the rear surface of Si provides hint of surface effect such as the generation of UCMu in vacuum. The yield of UCMu will be estimated via space–time resolution measurements in future research.