Electronic Structure and Pairing Instability of Heavy-Fermion Superconductor UTe₂

Spin-triplet superconductors are of extensive current interest because they are promising candidates to host topological states and Majorana fermions for quantum computation. The uranium-based heavy-fermion superconductor UTe₂ has recently been argued as a spin-triplet superconductor. However, the nature of the pairing state remains one of the most outstanding issues. Recent observations of antiferromagnetic fluctuations by neutron scattering are at odds with the notion of spin-triplet superconductivity driven by ferromagnetic interactions. In this work, we focus on some salient features of the electronic structure and magnetic properties of the system. In particular, the role of U-5f electron correlations in determining the nature of normal state and magnetic interactions will be elucidated within first-principles approaches. We will also discuss the superconducting pairing instability via a first-principles strongly correlated electron theoretical treatment, and its relationship to the underlying magnetic fluctuations.