Contribution to the Spontaneous Regeneration of the Centers of Exoemission of Electrons in Mg and Al

A plot of the variation of emission in Al after the operating voltage of the counter and the accelerating external field has been suppressed and the sample kept in the dark for 20 min, (b) is compared with the normal decay curve (a). The time-dependent decay may be regarded as a depopulation of traps. If the traps were populated only while the sample was being prepared, the level of (b) should be below that of (a), but it is not. Certain metal electrons are known to pass by tunneling through the barrier created by the metal-oxide junction, with high velocities and energies. They may be captured by lattice defects in the oxide at the interface, contributing to an increase of emitting centers. Centers spontaneously created are covered afterwards due to thickening of the oxide layer and the polyatomic gas layer adsorbed on the sample surfaces. 10 ref.--CIDA/AF.