Crystallographic disorder and electron scattering on structural two-level systems in ZrAs1.4Se0.5

TL;DR

This study investigates how structural disorder in ZrAs1.4Se0.5 influences electron scattering, revealing a resistivity minimum likely caused by interactions with two-level systems, despite typical metallic properties.

Contribution

It provides new insights into the role of crystallographic disorder and two-level systems in electron scattering within ZrAs1.4Se0.5.

Findings

Resistivity shows a shallow minimum at low temperatures unaffected by magnetic fields.

Significant disorder in the As-Se substructure confirmed by X-ray diffraction.

Interaction between conduction electrons and structural two-level systems causes the resistivity anomaly.

Abstract

Single crystals of ZrAs1.4Se0.5 (PbFCl type structure) were grown by chemical vapour transport. While their thermodynamic and transport properties are typical for ordinary metals, the electrical resistivity exhibits a shallow minimum at low temperatures. Application of strong magnetic fields does not influence this anomaly. The minimum of the resistivity in ZrAs1.4Se0.5 apparently originates from interaction between the conduction electrons and structural two-level systems. Significant disorder in the As-Se substructure is inferred from X-ray diffraction and electron microprobe studies.