The role of triakontadipoles in uranium-based magnetic superconductor materials
(English)Manuscript (preprint) (Other academic)
We investigate the ground state of the heavy-fermion actinide compounds UPd2Al3 , UNi2Al3 and UPt3 by means of electronic structure calculations including on-site correlation. The results are analyzed through multipole decomposition. In case of UPd2Al3 and UNi2Al3 we stabilize a solution with an antiferromagnetic arrangement of triakontadipoles with ordering vectors, respectively, q = (0, 0, 1/2 ) and q = ( 1/2 , 0, 1/2 ), whose total magnetic moment agrees with the experimental value. In case of UPt3 we identify a solution with a triakontadipole order whose symmetry is not compatible with the presence of a magnetic moment, in accordance with experiments that detect a very small value of the moment. The Fermi surfaces of the multipole dominated solutions have many common features with those obtained by conventional density functional methods. Finally, for URu2Si2 we are able to stabilize a new solution characterized by a q = (0, 0, 1/2 ) ordering of triakontadipoles and a symmetry that forbids a magnetic moment on uranium site. The Fermi surface of this solution is surprisingly similar to the one of the magnetic AF 1-q case in agreement with recent measurements.
Superconductivity, actinides, hidden order, correlated electrons
Condensed Matter Physics
Research subject Physics of Matter
IdentifiersURN: urn:nbn:se:uu:diva-132064OAI: oai:DiVA.org:uu-132064DiVA: diva2:356795