# First Principles Study of Electronic Structure and Fermi Surface in Rare-earth Filled Skutterudites RPt4Ge12

## TL;DR

This study uses first-principles calculations to analyze the electronic structure and Fermi surfaces of rare-earth filled skutterudites RPt4Ge12, revealing insights into their superconducting, thermoelectric, and correlated electron properties.

## Contribution

It provides a comprehensive theoretical analysis of electronic structures, Fermi surfaces, and the effects of f-orbital occupancy and Hubbard U in RPt4Ge12 skutterudites, advancing understanding of their properties.

## Key findings

- Fermi surfaces suggest multi-band superconductivity potential
- Density of states explains photoemission experiments
- Presence of pseudogaps may influence thermoelectric behavior

## Abstract

Experiments on rare-earth filled skutterudites demonstrate an intriguing array of thermodynamic, transport and superconducting properties, and bring to fore theoretical challenges posed by f-electron systems. First principle calculations based density functional theory and its extensions for strongly correlated systems such as the Hubbard U correction, provide valuable information about electronic structure that can be used to understand experiments. We present a comprehensive study of the electronic structure and Fermi surface of a series of rare earth filled skutterudites, RPt4Ge12 (where R = La, Ce, Pr), aimed at shedding light on: consequences of progressive increase of f-orbital occupancy in the series; the effects of the Hubbard parameter U; the Fermi surfaces, band structures and densities of states. The calculated Fermi surfaces may be relevant to the question of multi-band versus single-band superconductivity. Computed densities of states qualitatively explain the available resonant photoemission spectroscopy experiments, and (together with available specific heat measurements) provide estimates of the effective masses. We also show the existence of pseudogaps in the total density of states which may be relevant for the thermoelectric properties of these systems.