Research in the Synthesis of Rare Earth Compounds and a Study of Their Magnetic Optical and Semiconducting Properties
Abstract
The report discusses the development of an understanding of the chemical equilibria involved in the synthesis and crystal growth of pure and doped europium chalcogenides. Also explored was the relationship of defect structures and dopant concentration to the magnetic, optical and transport properties of these materials. Since nonstoichiometry is a significant factor determining the physical properties of the chalcogenides, vapor-solid equilibrium in EuSe was investigated. A study of the reaction between H2S and Eu2O3 was carried out to determine the amount of residual oxygen in EuS as a function of reaction temperature. Magnetic measurements for the system Eu(1 - x) Gd(x)S over the range x = .03 to .36 show ferromagnetic properties with an increase in Curie temperature by a factor of three times over that of insulating EuS. Transport properties in both metallic and semiconducting europium chalcogenides are under investigation. In the former the effort is directed towards understanding the exchange interactions between conduction electrons and the localized spin of the rare earths. In the latter, the purpose is to distinguish between two basic transport processes, hopping and band conductivity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1971
- Accession Number
- AD0717369
Entities
People
- F. Holtzberg
- Michael W. Shafer
- S. Von Molnar
- T. Penney
- T. R. Mcguire
Organizations
- IBM Thomas J. Watson Research Center