Mechanism of anomalous penetration of positrons through a crystal
Dekhtyar I.Ya. , Adonkin V.T. , Madatova E.G., Silant'ev V.I., Dlubek G.
The angular-correlation curves of annihilation photons in an Si crystal are investigated at 11, 80, and 300 K. At low temperatures, besides the narrow component corresponding to Ps atoms, satellites are observed and attest to the derealization of the Ps atoms. The penetration of the positron through the crystal is attributed to realization of a quantum mechanism of Ps diffusion.