Unusual temperature dependence of the spectral weight near the Fermi level of NdNiO3 thin films

TL;DR

This study examines how the spectral weight near the Fermi level in NdNiO3 thin films varies with temperature, revealing unusual behavior and thermal hysteresis across the metal-insulator transition.

Contribution

It provides new insights into the temperature-dependent spectral weight behavior near the Fermi level in NdNiO3, highlighting regimes independent of the MIT.

Findings

Spectral weight exhibits thermal hysteresis similar to dc conductivity.

Two distinct regimes of spectral loss near the Fermi level identified.

One regime's temperature evolution is independent of the metal-insulator transition.

Abstract

We investigate the behavior of the spectral weight near the Fermi level of NdNiO3 thin films as a function of temperature across the metal-to-insulator transition (MIT) by means of ultraviolet photoelectron spectroscopy. The spectral weight was found to exhibit thermal hysteresis, similar to that of the dc conductivity. A detailed analysis of the temperature dependence reveals two distinct regimes of spectral loss close to the Fermi level. The temperature evolution of one regime is found to be independent from the MIT.