Temperature evolution of structural and magnetic properties of stoichiometric LiCu2O2: correlation of thermal expansion coefficient and magnetic order

TL;DR

This study investigates how the structural and magnetic properties of LiCu2O2 change with temperature, revealing magnetoelastic coupling and a magnetic anomaly at 150 K through crystallographic, magnetic, and thermal expansion analyses.

Contribution

It provides new insights into the temperature-dependent magnetoelastic coupling and magnetic anomalies in stoichiometric LiCu2O2, linking thermal expansion behavior with magnetic ordering.

Findings

Magnetic ordering occurs below 25 K.

Magnetoelastic coupling affects thermal expansion along the c-axis.

Anomalous thermal expansion indicates magnetic anomaly at 150 K.

Abstract

Temperature-dependent crystallographic and magnetic studies on stoichiometric single crystals of LiCu2O2 are reported. The magnetic properties are similar to earlier findings demonstrating antiferromagnetic ordering below 25 K. Evidence of magnetoelastic coupling is observed in the thermal expansion along the c-direction; not only at the low temperature antiferromagnetic transitions, but an anomalous behavior of the thermal expansion indicate magnetoelastic coupling also to the magnetic ordering related to a weak spontaneous magnetic moment appearing at 150 K. Ac-susceptibility measurements at different frequencies and superposed dc- fields are employed to further characterize this magnetic anomaly.