Transport properties and electronic structure of new rare earth-copper chalcogenides
Authors:
- Irena Jacyna-Onyszkiewicz,
- M. Zimpel,
- M.A. Obolensky,
- Yu.B. Poltoracky,
- S. Starodub,
- Stanisław Robaszkiewicz
Abstract
New rare earth-copper chalcogenides: La2CuS4+δ and Y2Cu2S5+δ with the chemical patterns corresponding to the extensively studied copper oxides La2CuO4+δ and Y2Cu2S5, have been synthesised and investigated with respect to their electronic structure, electric transport and magnetic properties. These properties are found to be dependent on the technology of their production and sulphur content. Surprisingly, the sulphur-rich systems are insulators with the activation energy EA∼0.2-0.3 eV, whereas the compounds synthesised from substrate amounts, corresponding to the stoichiometry of La2CuS4 and Y2Cu2S5, exhibit metallic conductivity with a linear temperature dependence of resistivity in almost entire temperature range studied (4.2-300 K). For additionally soaked Y2Cu2S5 samples, a broad metal-nonmetal transition taking place with increasing temperature has been detected between 170 and 210 K. XPS investigation supported by susceptibility measurements indicate that in Y2Cu2S5+δ (both metallic and nonmetallic samples) a part of copper atoms occur in Cu2+ valence state, whereas in the metallic La2CuS4+δ(δ ≈ 0) the copper valence state is mainly Cu1+.
- Record ID
- UAM6834ef4ae4754e4d8f5a824ea38d958d
- Author
- Journal series
- Physica B-Condensed Matter, ISSN 0921-4526
- Issue year
- 1997
- Vol
- 239
- Pages
- 283-292
- ASJC Classification
- ; ;
- DOI
- DOI:10.1016/S0921-4526(97)00338-4 Opening in a new tab
- Language
- (en) English
- Score (nominal)
- 0
- Score source
- journalList
- Publication indicators
- = 2; : 2014 = 0.942; : 2006 (2 years) = 0.872 - 2007 (5 years) =0.756
- Uniform Resource Identifier
- https://researchportal.amu.edu.pl/info/article/UAM6834ef4ae4754e4d8f5a824ea38d958d/
- URN
urn:amu-prod:UAM6834ef4ae4754e4d8f5a824ea38d958d
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or PerishOpening in a new tab system.