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Magnetic Phase Transitions in the double spin-chains compound $\rm LiCu_2O_2$

B. Roessli·U. Staub·A. Amato·D. Herlach·P. Pattison·K. Sablina·G. A. Petrakovskii
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Abstract

We report high-resolution x-ray diffraction, muon-spin-rotation spectroscopic and specific heat measurements in the double spin-chains compound $\rm LiCu_2O_2$. The x-ray diffraction results show that the crystal structure of $\rm LiCu_2O_2$ ~is orthorhombic down to T=10K. Anisotropic line-broadening of the diffraction peaks is observed, indicating disorder along the spin chains. Muon spin relaxation and specific heat measurements show that $\rm LiCu_2O_2$ ũndergoes a phase transition to a magnetic ordered state at $\rm T_1\sim24K$. The specific heat data exhibits a second $\rm λ$-like peak at $\rm T_2\sim22.5 K$, which increases with increasing magnetic field similarly way to that found in spin-ladder compounds.

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B. Roessli, U. Staub, A. Amato, D. Herlach, P. Pattison, K. Sablina, G. A. Petrakovskii. 2000-10-26. Magnetic Phase Transitions in the double spin-chains compound $\rm LiCu_2O_2$. https://doi.org/10.1016/s0921-4526(00)00574-3

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