Electric Field Dependence

of Diamagnetic Muon Asymmetry in

Gallium Arsenide

At a temperature of 50K, in a transverse magnetic field of 100G, the diamagnetic muon asymmetry is a strong function of applied electric field.  This is because the muon attracts free electrons liberated in its ionization track and captures them after it stops, to form the paramagnetic muonium (Mu) atom.   An applied electric field can compete with the muon's Coulomb attraction for the electron as long as the muon-electron distance is not too short; thus the characteristic field required to quench delayed Mu formation is a measure of the mean muon-electron distance, which in this case is estimated to be 50-100 nm.   The asymmetry in the E-field dependence (a positive E is in the direction of the muon's original momentum) indicates that the electrons are left predominantly behind the muon.
Author: JHB.     Figure created 1997.     See TRIUMF Expt 775.
Prepared by Jess H. Brewer

Last modified: Thu Aug 13 13:32:27 PDT 1998