UBe13 and U1-xThxBe13: Unconventional Superconductors

TL;DR

This review discusses the properties of UBe13 and Th-doped UBe13, emphasizing their unconventional superconductivity and summarizing decades of research to understand their complex behaviors.

Contribution

It provides a comprehensive comparison of UBe13 and Th-doped UBe13, highlighting their unconventional superconducting features and proposing directions for future experiments.

Findings

UBe13 is an unconventional heavy fermion superconductor.

Th-doping enhances the complexity of superconductivity in UBe13.

Decades of characterization support the unconventional nature of these materials.

Abstract

UBe13 was the second discovered heavy fermion superconductor, and numerous pieces of evidence exist that imply that it is an unconventional (non-BCS, non-s wave pairing symmetry) superconductor. Exhibiting even more signs of unconventional superconductivity, Th-doped UBe13 is perhaps the most puzzling of any of the unconventional superconductors. This review considers both the parent, undoped compound as well as the more interesting Th-doped UBe13. After summarizing the rather thorough characterization, which because of the interest in these compounds has continued from their discovery in 1983 and 1984 to date, these properties are compared with a recent template for determining whether a superconductor is unconventional. Finally, further experiments are suggested.