The calcium effect on the thermopower, critical temperature and charge-carrier system parameters in the Y0.75-xCaxPr0.25Ba2Cu3Oy HTSC-system

Physics of Complex Systems

Виталий Эдуардович Гасумянц¹ 

[1] Peter the Great St. Petersburg Polytechnic University;

关键词: high-temperature superconductors;    calcium doping;    critical temperature;    thermopower;    narrow-band model;    normal-state energy spectrum;   

DOI  :  10.33910/2687-153X-2020-1-4-142-149

来源: DOAJ

【 摘 要 】

Superconducting properties and thermopower temperature dependences for two series of ceramic samples with Y0.75-xCaxPr0.25Ba2Cu3Oy (x = 0–0.25) compositions are experimentally investigated. Thermopower temperature dependences are analysed using the phenomenological narrow-band model. The normal state energy spectrum and the charge-carrier system parameters including the Fermi level position are determined and the doping influence on their value is discussed. It is shown that the Fermi level position in Y0.75-xCaxPr0.25Ba2Cu3Oy samples is determined by its pinning inside a local peak in the density-of-states function formed due to increasing calcium content. The influence of the observed normal-state energy spectrum modification on the critical temperature in the studied system is discussed.

【 授权许可】

Unknown