The Search for magnetic order in -Pu metal using muon spin relaxation

Heffner, R. H.; Oishi, Kazuki; Fluss, M. J.*; Morris, G. D.*; MacLaughlin, D. E.*; Shu, L.*; Chung, B. W.*; McCall, S. K.*; Bauer, E. D.*; Sarrao, J. L.*; et al.

Journal of Alloys and Compounds, 444-445, p.80 - 83, 2007/10

https://doi.org/10.1016/j.jallcom.2006.12.026

We summarize the results of muon spin relaxation (SR) measurements carried out in- and -Pu and in the superconducting state ofPuCoGa. In Pu metal, interest has centered on whether or not magnetic order exists in the hightemperature fcc phase,The Pu metal studies were designed to search for evidence of magnetic ordering, andhave set the most stringent limits to date for the ordered moment. In PuCoGa the temperature dependence of themagnetic penetration depth (T) was investigated in a fresh sample and again in the same sampleafter 400 days of aging. We find (T) T for T Tc/2, indicating a line of nodes in thesuperconducting order parameter. Remarkably, the temperature dependence of (T) is littlechanged even after significant radiation damage.