Crystal and electronic structure of high temperature superconducting compound Y1-xCaxBa2Cu3Oy in the temperature interval 80-300 K / Titova Svetlana G.,Lukoyanov Alexey V.,Pryanichnikov Stepan V.,Cherepanova Lubov A.,Titov Alexander N. // JOURNAL OF ALLOYS AND COMPOUNDS. - 2016. - V. 658, l. . - P. 891-897.

ISSN/EISSN:

0925-8388 / 1873-4669

Type:

Article

Abstract:

For Y1-xCaxBa2Cu3Oy with varying oxygen and calcium content, the change of crystal structure at cooling from room temperature to 80 K has been investigated. The main change is associated with a shift of apical oxygen atoms. Using determined unit cell parameters as function of temperature, the coefficients of linear thermal expansion have been calculated as alpha(X) = 1/X.(dX/dT), where. X = a, b, c - unit cell dimensions. For the compound without calcium all alpha(X) values demonstrate anomalous behavior such as growing at cooling in temperature interval T-1 divided by T2 similar to 150 divided by 225 K. The calculation of electronic structure at temperatures above, below and within this interval shows the appearance of the electronic states density peak for Ba and O4 atoms. It is explained by the localization of charge carriers with the participation of the lattice distortion in a form of apical CueO bond compression. As the material Y0.9Ca0.1Ba2Cu3Oy regardless of the oxygen content possess low and constant coefficient of thermal expansion along all crystallographic directions, that makes this material suitable for superconducting films and other composites. (C) 2015 Elsevier B.V. All rights reserved.

Author keywords:

Superconductors; Crystal structure; Electronic band structure; Thermal expansion ITINERANT HOLES; CHARGE ORDER; DEPENDENCE; CA; YBA2CU3O7-DELTA; SPECTROSCOPY; TRANSITION; PSEUDOGAP; ANOMALIES; DENSITY

DOI:

10.1016/j.jallcom.2015.11.019

Web of Science ID:

ISI:000366940100124

Соавторы в МНС:

Другие поля

Поле	Значение
Month	FEB 15
Publisher	ELSEVIER SCIENCE SA
Address	PO BOX 564, 1001 LAUSANNE, SWITZERLAND
Language	English
EISSN	1873-4669
Keywords-Plus	ITINERANT HOLES; CHARGE ORDER; DEPENDENCE; CA; YBA2CU3O7-DELTA; SPECTROSCOPY; TRANSITION; PSEUDOGAP; ANOMALIES; DENSITY
Research-Areas	Chemistry; Materials Science; Metallurgy \& Metallurgical Engineering
Web-of-Science-Categories	Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy \& Metallurgical Engineering
Author-Email	sgtitova@mail.ru
ResearcherID-Numbers	Lukoyanov, Alexey/J-8069-2013 Titov, Alexander/K-4328-2013
ORCID-Numbers	Lukoyanov, Alexey/0000-0003-4459-0893 Titov, Alexander/0000-0003-3636-2604
Funding-Acknowledgement	state project of IMET UrD RAS {[}0396-2014-0001]; ``Dinasty{''} foundation; UrD RAS {[}15-17-2-16]
Funding-Text	The work was performed in accordance of state project No 0396-2014-0001 of IMET UrD RAS, at partial financial support of UrD RAS, project No 15-17-2-16, use of the equipment of the Center ``Ural-M{''}. A.V.L. thanks the ``Dinasty{''} foundation for support.
Number-of-Cited-References	42
Usage-Count-Last-180-days	1
Usage-Count-Since-2013	14
Journal-ISO	J. Alloy. Compd.
Doc-Delivery-Number	CZ2MU