Monocrystal high-temperature superconductors (HTSC) with stratified structure are suitable objects for the investigation of effects of dimensional quantization, because in this case there is no necessity in the preparing of monolayer specimens, homogeneous by thickness, for providing total positron absorption in the HTSC layer. In present paper the possibility of detection of quantum dimensional effects (QDE) in monocrystal HTSC is theoretically shown for the first time. It has been established, that the spectrum of angular distribution of annihilation photons (ADAP) for monocrystal HTSC with stratified structure has strongly anisotropic character, namely, when the axis of the detection system of the installation for ADAP measurements is perpendicular to the projection of total photon pulse on the chosen z-direction in pulse space (R1), the ADAP curve has pronounced step-like character in the range of pulses which corresponds to the positions of occupied electron sub-bands. The charge states of Cu(1) atoms in superconductive chains are considered on the example of Y-Ba-Cu-O oxide and experimental results of the positron probing of core d-electrons at the HTSC is discussed. For this particular case, when the projection of total photons pulse is oriented along the conductive layer, ADAP curve is similar to the inverted parabola(R2). It has been shown, that R2 is significantly shorter than R1.It has been established that the half-width of R2 does not depend on electron characteristics of superconductive layer in HTSC. It is also necessary to take into account the influence of the substrate, as well as the decreasing of anisotropy of ADAP that both are connected with the presence of oxygen bridges in the structure of HTSC monocrystals and with disordering of separate domains.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/1301 must be provided.

1. CHARACTERIZATION OF NANOSTRUCTURED METAL PARTICLES BY POSITRON ANNIHILATION SPECTROSCOPY