Abstract:
The use the limb - difference scheme for calculating of the thermally stimulated current of depolarization allows to identify the characteristic of low temperature relaxators size effects. These effects were caused by anormal displacement of the theoretical maximum termo depolarization current density at lower temperatures of (12 – 14) K with increasing of amplitude maximum on one - two orders of magnitude on a nanometer crystal layers with hydrogen bonds. On the model of a multi pit potential of relief with rectangular shape and ohmic contacts at the boundaries of the crystal it is shown that decreasing of potential pits number energy band width is decreasing. But the minimum distance between adjacent energy bands is increasing, the energy spectrum becomes quasi discrete, potential barrier transparency is increasing, the tunneling causes quantum effects are enhancing. It was established that with locking pins at the boundary of crystal layers in the nanometer layers (3 nm) in comparing with crystals of thickness 30microns the maximum number of associated energy levels of relaxators with low temperature is decreasing by 99% from the current thermo depolarization theoretical maximum displacement toward low temperature of (65 -75) K. Whereas increasing of density amplitude TSDC on (3 – 4) orders of magnitude, while the high-temperature defects of Bjerrum increase only on 1% when and temperature shift is on (0.1 – 1) K at a constant amplitude. Therefore it can be argued that in the nanometer crystals with hydrogen ties of polarization at very low temperatures (4 – 25) K is caused by nanoclusters.
