Quantum Critiality and Collective Effects in Low Dimensional Magnet CuGeO3 Probed by High Frequency EPR

TL;DR

This study investigates quantum critical behavior and collective effects in doped CuGeO3 crystals using high-frequency EPR, revealing critical exponents and magnetic properties related to low-dimensional magnetism.

Contribution

It provides new experimental data on quantum criticality and magnetic exponents in doped CuGeO3, highlighting the role of staggered magnetic moments and competing magnetic effects.

Findings

Quantum critical behavior observed between 1-40 K.

Critical exponents determined: a=0.34 and a=0.31.

Staggered magnetic moments mainly along the b axis.

Abstract

For the CuGeO3 single crystals doped with 1% of Fe the quantum critical behavior in a wide temperature range 1-40 K is reported. The critical exponents for susceptibility along different crystallographic axes are determined: a=0.34 (B //a and B //c) and a=0.31 (B //b). The description of the temperature dependences of the line width and g-factor could be obtained in the OA theory assuming that staggered component of the magnetic moment is located predominantly along b axis. Possible arguments favoring the competition between effects of the staggered field and antiferromagnetic ordering are provided.