Thermal conductivity of pure and Zn-doped LiCu_2O_2 single crystals

TL;DR

This study investigates the low-temperature thermal conductivity of pure and Zn-doped LiCu_2O_2 single crystals, revealing distinct phonon and magnon contributions and how Zn doping and magnetic fields influence these heat transport mechanisms.

Contribution

It provides new insights into phonon and magnon heat transport in LiCu_2O_2, highlighting the effects of Zn doping and magnetic fields on thermal conductivity.

Findings

Double-peak behavior in thermal conductivity at 48 K and 14 K.

High-T peak attributed to phonon transport, low-T to magnon transport.

Magnetic field suppresses the low-T magnon-related peak.

Abstract

We report a study of the low-temperature thermal conductivity (\kappa) of pure and Zn-doped LiCu_2O_2 single crystals. The \kappa(T) of pure LiCu_2O_2 single crystal shows a double-peak behavior, with two peaks locating at 48 K and 14 K, respectively. The different dependences of the peaks on the Zn concentration indicate that the high-T peak is likely due to the phonon transport while the low-T one is attributed to the magnon transport in the spin spiral ordering state. In addition, the magnetic field can gradually suppress the low-T peak but does not affect the high-T one; this further confirms that the low-T peak is originated from the magnon heat transport.