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arXiv · 1412.2988

Low-temperature ordered phases of the spin-$\frac{1}{2}$ XXZ chain system Cs$_2$CoCl$_4$

O. Breunig·M. Garst·A. Rosch·E. Sela·B. Buldmann·P. Becker·L. Bohaty·R. Müller·T. Lorenz
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Abstract

In this study the magnetic order of the spin-1/2 XXZ chain system Cs$_2$CoCl$_4$ in a temperature range from 50 mK to 0.5 K and in applied magnetic fields up to 3.5 T is investigated by high-resolution measurements of the thermal expansion and the specific heat. Applying magnetic fields along a or c suppresses $T_\textrm{N}$ completely at about 2.1 T. In addition, we find an adjacent intermediate phase before the magnetization saturates close to 2.5 T. For magnetic fields applied along b, a surprisingly rich phase diagram arises. Two additional transitions are observed at critical fields $μ_0 H_{SF1}\simeq 0.25$ T and $μ_0 H_{SF2}\simeq 0.7$ T, which we propose to arise from a two-stage spin-flop transition.

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O. Breunig, M. Garst, A. Rosch, E. Sela, B. Buldmann, P. Becker, L. Bohaty, R. Müller, T. Lorenz. 2014-12-09. Low-temperature ordered phases of the spin-$\frac{1}{2}$ XXZ chain system Cs$_2$CoCl$_4$. https://doi.org/10.1103/physrevb.91.024423

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