2008/07/28 by S. A. J. Kimber, Simon A. J. Kimber, D. N. Argyriou +15 · 1 citation
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Magnetic and transport properties of perovskites and related materials #Rare-earth and actinide compounds #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.78.140503
arxiv created 2008/07/28 · openalex publication_date 2008/10/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report the structure and magnetism of PrFeAsO, one of the parent phases of the Fe-As family of superconductors, as measured by neutron powder diffraction. In common with other REFeAsO materials, a tetragonal-orthorhombic phase transition is found on cooling below 136 K and striped Fe magnetism with k=(1,0,1) is detected below \ensuremath∼85 K. Our magnetic order-parameter measurements show that the ordered Fe moment along the a axis reaches a maximum at \ensuremath∼40 K, below which an anomalous expansion of the c axis sets in that results in a negative thermal volume expansion of 0.015% at 2 K. We propose that this effect, which is suppressed in superconducting samples, is driven by a delicate interplay between Fe and Pr ordered moments.