PuPt2In7: a computational and experimental investigation

TL;DR

This study combines experimental and computational methods to investigate PuPt2In7, revealing heavy fermion behavior, electronic structure details, and the absence of superconductivity despite similarities to related compounds.

Contribution

It provides the first combined experimental and theoretical analysis of PuPt2In7, including synthesis, characterization, and electronic structure calculations, and compares it to related heavy-fermion materials.

Findings

PuPt2In7 is non-superconducting and non-magnetic down to 2 K.

It exhibits heavy fermion behavior with a large Sommerfeld coefficient.

The electronic structure shows strong c-f hybridization similar to superconducting PuCoIn5.

Abstract

Flux-grown single crystals of PuPt$_2$In$_7$ are characterized and found to be both non-superconducting and non-magnetic down to 2 K. The Sommerfeld specific heat coefficient of $\sim 250$ mJ/mol K$^2$ indicates heavy fermion behavior. We report the results of generalized gradient approximation (GGA)+$U$ calculations of PuPt$_2$In$_7$ and as yet unsynthesized isovalent PuPt$_2$Ga$_7$. The strength of the $c$-$f$ hybridization of PuPt$_2$In$_7$ is similar to the PuCoIn$_5$ superconductor. The bare and $f$-weighted susceptibility within the constant-matrix-element approximation is calculated, showing a maximum along the $q_z$ direction at $q_x = q_y = 0.5$. A similar and slightly stronger maximum is also found in the structurally related heavy-fermion materials PuCoGa$_5$ and PuCoIn$_5$. The absence of superconductivity in PuPt$_2$In$_7$ is examined based on the results of our calculations.