Continuous metal-insulator transition of the antiferromagnetic perovskite NaOsO3

TL;DR

This paper investigates the continuous transition from metal to insulator in NaOsO3, highlighting the role of antiferromagnetic correlations without lattice anomalies, and demonstrating a full band gap opening at the transition.

Contribution

It provides experimental evidence of a continuous metal-insulator transition driven by magnetic correlations in NaOsO3, with no detectable lattice distortions.

Findings

NaOsO3 exhibits a continuous metal-insulator transition at 410 K.

The transition involves a full opening of the electronic band gap.

Lattice anomalies are not observed near the transition temperature.

Abstract

Newly synthesized perovskite NaOsO3 shows Curie-Weiss metallic nature at high temperature and suddenly goes into an antiferromagnetically insulating state at 410 K on cooling. Electronic specific heat at the low temperature limit is absent, indicating that the band gap fully opens. In situ observation in electron microscopy undetected any lattice anomalies in the vicinity of the transition temperature. It is most likely that the antiferromagnetic correlation plays an essential role of the gap opening.