Coexistence of dimerization and long-range magnetic order in the quantum antiferromagnetic compound LiCu2O2: inelastic light scattering study

TL;DR

This study uses Raman scattering to reveal the coexistence of long-range magnetic order and dimerization in LiCu$_{2}$O$_{2}$, highlighting the role of magnetic impurities and complex phase transitions.

Contribution

It provides new insights into the magnetostructural properties of LiCu$_{2}$O$_{2}$, demonstrating the coexistence of magnetic phenomena and impurity effects through inelastic light scattering.

Findings

Confirmation of two magnetic transitions at 9 K and 24 K

Observation of two magnetic excitations at 100 and 110 cm$^{-1}$

Impurities influence the magnetic phase transition

Abstract

Raman scattering studies of the frustrated spin chain system LiCu$_{2}$O$_{2}$ are reported. Two transitions into a magnetically ordered phase (taken place at temperatures $\sim$ 9 K and $\sim$ 24 K) have been confirmed from the analysis of optical properties of the samples. Interestingly, two different magnetic excitations, seen at 100 and 110 cm$^{-1}$ in the magnetically ordered phase superimpose each other independently, indicating a coherent coexistence of long-range magnetic order and dimerization. The observed phenomenon is attributed to magnetostructural peculiarities of LiCu$_{2}$O$_{2}$ leading to the intrinsic presence of nonmagnetic impurities on a nanometer scale. Furthermore, magnetic impurities play a significant role in driving the transition from an incommensurate state to a N\'{e}el ordered one at 9 K.