Strain induced renormalization of transport properties in UPt3 thin films

Abstract

The growth of sputter deposited UPt3 thin films on AlcOa (i0i2), LaAIOa (111) and SrTiO3 (111) was investigated. We found strongly 0001-textured growth of UPta in a small compositional range of 23 -25% uranium content. For A1203-and LaAlO3-substrates no in-plane order could be observed whereas epitaxial growth was initiated on SrTiO3 (111). The growth can be identified as Vollmer-Weber like resulting in the formation of large lateral strain as a consequence of the growth mode and a lattice misfit of -4 . 3 % between UPt3 (0001) and SrTiOa (111). Strong deviations from the typical heavy-fermion characteristics in electronic transport properties like resistivity, magnetoresistivity and Hall-effect are attributed to changes of the hybridization between the localized 5f-and itinerant states.*

Advances in actinide thin films: synthesis, properties, and future directions

“…Brun, Cren, and Roditchev summarized the superconductivity of 2D materials as a strong case for epitaxial monolayer materials growth [199]. Huth et al demonstrated deviations from typical heavy-fermion material characteristics in superconducting UPt 3 [91], attributed to the hybridization of 5f electrons and itinerant states, although the nature of the pairing mechanism is still under debate. Superconductivity was also observed in UPd 2 Al 3 [38] and UNi 2 Al 3 [40], while the optical conductivity of this last compound was studied by Ostertag et al using terahertz frequencies [200].…”