Electronic Structure of Noncentrosymmetric Superconductor Li$_2$(Pd$_x$Pt$_{1-x}$3)B Studied by Photoemission Spectroscopy

TL;DR

This study investigates the electronic structure of the noncentrosymmetric superconductor Li$_2$(Pd$_x$Pt$_{1-x}$)B using photoemission spectroscopy, revealing how Pt incorporation affects the band structure and density of states.

Contribution

It provides experimental photoemission data and analysis on the electronic structure evolution with Pt substitution in Li$_2$(Pd$_x$Pt$_{1-x}$)B, aligning with band calculations.

Findings

Identification of valence band features consistent with calculations.

Observation of smooth electronic structure evolution with Pt doping.

Insights into the role of antisymmetric spin-orbit coupling.

Abstract

We have performed x-ray photoemission spectroscopy on the system of noncentrosymmetric superconductor, Li$_2$(Pd$_x$Pt$_{1-x}$3)B. For Li$_2$Pt$_3$B, we found 2 major peaks with 2 other weak components, and the band calculations were in agreement with the observation. The assignment of valence band features using the calculated partial density of states determined that Pt 5d and B 2p contribute to the density of states at the Fermi level. The effect of antisymmetric spin-orbit coupling on the band structure might have been probed, and the analysis on the effect of Pt incorporation into the system indicates the smooth evolution of electronic structures. We presented the measurements of core levels (Pd 3d, Pt 4f, and B 1s) and discussed the chemical bonding states and electronic structures from them.