Verification Makhov,s profile for slow positron in Germanium

Abstract

In this paper the mean penetration depths z0 and Makhov (Implantation) profile I(z,E) were evaluated for low energies positrons(1.5-30/keV)by using a distribution function of Valkealahti - Nieminen for Germanium for different thicknesses:0.2, 0.4,0.8,1.2,1.4,1.6 μm. The obtained results reveals that the values of Makhov,s profile decreased exponentialy with increasing the positron energy and profile depths increasing linearly with increasing the incident energy. The shape of the Makhov,s profile reflects the shape of the energy spectrum of the positrons, which indicates the annihilation of positrons inside the material where its wavefunction is delocalized.