Manifestation of lattice distortions in the O 1s spectra in Ca1-xSrxRuO3

TL;DR

This study explores how temperature influences the electronic and crystal structures of Ca1-xSrxRuO3, revealing lattice distortions affect O 1s spectra and electronic behavior, especially in Ca-rich samples.

Contribution

It demonstrates the link between lattice distortions and electronic properties through temperature-dependent O 1s spectra analysis in Ca1-xSrxRuO3.

Findings

O 1s spectra show distinct features in Ca-doped samples.

Temperature reduces energy separation of spectral features in Ca-rich samples.

Lattice distortions are connected to non-Fermi liquid behavior.

Abstract

We investigate the effect of temperature on the electronic and crystal structures of Ca1-xSrxRuO3 via the evolution of O 1s core level spectra as a function of temperature and composition, x. O 1s spectra in SrRuO3 exhibit a dominant sharp feature at all the temperatures with a small trace of impurity feature at higher binding energies. The spectra in Ca doped samples, however, exhibit two distinct features. Analysis of the experimental spectral functions and the band structure results suggest that different Madelung potential at the two types of oxygen sites in the orthorhombically distorted structure leads to such splitting in the O 1s spectra. Interestingly, the energy separation of these two features becomes smaller at low temperatures in the Ca dominated samples concomitant to the observation of non-Fermi liquid behavior in their bulk properties. Such temperature evolution, thus, indicates a direct connection of the lattice degrees of freedom with the electronic properties of these compounds.