ISSN:
1573-7357
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Physik
Notizen:
Abstract We review our recent studies of muonium diffusion in cryocrystals. Atomic muonium (Mu = μ + e − ) may be considered as a light isotope of hydrogen and so provides the prototypical light interstitial defect in these sytems, themselves the simplest of insulators. Experiments using the muon spin relaxation techniques in transverse and longitudinal (zero) magnetic fields reveal tunneling motion at low temperatures, governed by various mechanisms of phonon scattering. The results are compared with the current theories of quantum diffusion in insulators. A two–phonon scattering mechanism is found to dominate at low temperatures in solid nitrogen, methanes and carbon dioxide, whereas a one–phonon interaction provides the main channel at temperatures comparable to the Debye temperature in solid nitrogen, xenon and krypton. Particular attention is devoted to quantum diffusion processes in the presence of static crystal disorder. At low temperatures, the muonium diffusion can no longer be described in terms of a single correlation time. The localization and delocalization effects in the Mu diffusion in such inhomogeneous crystals are discussed in detail. Finally, the authors give an analysis of trapping phenomena for muonium in insulators.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1023/A:1022275317457
Permalink
