First-principles study of the electronic structure and the Fermi surface in rare-earth filled skutterudites RPt4Ge12

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.

Electron–phonon superconductivity in C-doped topological nodal-line semimetal Zr5Pt3: a muon spin rotation and relaxation (μSR) study

“…The electronic band structure, partial DOS, and Fermi surface of Although its complex, disconnected multiband nature, the homogeneous distribution of the electronic character of the Fermi surface shows an evident contrast from the usual signature presented by the Fermi surface of multiband superconductors, which generally presents very distinct orbital characters and an anisotropic hybridization on distinct sheets, and, as consequence, the average of the electron-phonon scattering connecting different points at Fermi surface are disjointed relative to the band index [63][64][65][66][67][68][69][70][71]. The mutual monotonic decrease of the DOS at the Fermi level and the observed superconducting critical temperature with the carbon doping [25] is compatible with the BCS theory as well.…”

New Insights on the Electronic-Structural Interplay in LaPdSb and CePdSb Intermetallic Compounds

“…To obtain a deeper insight into the electronic structure around the M point, in Figure 5 , we show the electronic band structure with the atomic projections (fat band representation [ 25 , 40 , 41 ]). Independently of the puckering strength, we see that bands around the Fermi energy have contributions mostly from La and Pd ions (moreover, inspecting further the band character, we find mostly La-d and Pd-d orbital character in this energy range).…”

Electron-phonon superconductivity in C-doped topological nodal-line semimetal Zr$_5$Pt$_3$: A muon spin rotation and relaxation ($μ$SR) study

“…The electronic band structure, partial density of states (DOS), and Fermi surface of Zr 5 Pt Although its complex, disconnected multiband nature, the homogeneous distribution of the electronic character of the Fermi surface shows an evident contrast from the usual signature presented by the Fermi surface of multiband superconductors, which generally presents very distinct orbital characters and an anisotropic hybridization on distinct sheets, and, as consequence, the average of the electron-phonon scattering connecting different points at Fermi surface are disjointed relative to the band index [60][61][62][63][64][65][66][67][68]. The mutual monotonic decrease of the DOS at the Fermi level and the observed superconducting critical temperature with the carbon doping [25] is compatible with the BCS theory as well.…”