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arXiv · 1004.2373

Heat capacity uncovers physics of a frustrated spin tube

N. B. Ivanov·J. Schnack·R. Schnalle·J. Richter·P. Koegerler·G. N. Newton·L. Cronin·Y. Oshima·Hiroyuki Nojiri
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Abstract

We report on refined experimental results concerning the low-temperature specific heat of the frustrated spin tube material [(CuCl2tachH)3Cl]Cl2. This substance turns out to be an unusually perfect spin tube system which allows to study the physics of quasi-one dimensional antiferromagnetic structures in rather general terms. An analysis of the specific heat data demonstrates that at low enough temperatures the system exhibits a Tomonaga-Luttinger liquid behavior corresponding to an effective spin-3/2 antiferromagnetic Heisenberg chain with short-range exchange interactions. On the other hand, at somewhat elevated temperatures the composite spin structure of the chain is revealed through a Schottky-type peak in the specific heat located around 2 K. We argue that the dominating contribution to the peak originates from gapped magnon-type excitations related to the internal degrees of freedom of the rung spins.

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N. B. Ivanov, J. Schnack, R. Schnalle, J. Richter, P. Koegerler, G. N. Newton, L. Cronin, Y. Oshima, Hiroyuki Nojiri. 2010-04-14. Heat capacity uncovers physics of a frustrated spin tube. https://doi.org/10.1103/physrevlett.105.037206

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