MBE growth and characterisation of light rare-earth superlattices

Autor: R A Cowley, M. R. Wells, J.A. Simpson, D. F. McMorrow, R.C.C. Ward, C. Bryn-Jacobsen, J.P Goff
Rok vydání: 2016
Předmět:
DOI: 10.1016/0040-6090(95)07071-0
Popis: The molecular beam epitaxy growth techniques which have already successfully produced a range of heavy rare-earth superlattices have now been extended to produce superlattices of two light rare-earth elements, Nd Pr , as well as superlattices and alloy films of a heavy/light system, Ho Pr . High-resolution X-ray diffraction analysis shows the Nd Pr superlattices to be of high structural quality, while the Ho Pr superlattices are significantly less so. In the Ho Pr superlattices, Pr is found to retain its bulk dhcp crystal structure even in thin layers (down to 6 atomic planes thick) sandwiched between thick layers of hcp Ho. In addition, neutron diffraction studies of the Ho Pr superlattices have shown that the helical Ho magnetic order is not coherent through the dhcp Pr layers, in contrast to previous hcp hcp superlattices Ho Y , Ho Lu and Ho Er . The series of Ho:Pr alloy films has shown structural trends similar to bulk alloys, with a range of compositions between Ho0.55Pr0.45 and Ho0.35Pr0.65 where the Sm δ-structure is stable, separating more extensive regions of hep and dhcp solid solutions.
Databáze: OpenAIRE