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BaCu_2Si_2O_7: a new quasi 1-dimensional S = 1/2 antiferromagnetic chain system

I. Tsukada·Y. Sasago·K. Uchinokura·A. Zheludev·S. Maslov·G. Shirane·K. Kakurai·E. Ressouche
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Abstract

The new antiferromagnetic (AF) compound BaCu_2Si_2O_7 is studied by magnetic susceptibility and neutron scattering techniques. The observed behavior is dominated by the presence of loosely coupled S=1/2 chains with the intrachain AF exchange constant J = 24.1 meV. Long-range Neel ordering is observed below Tn = 9.2 K. The results are discussed within the framework of the Mean Field-RPA model for weakly interacting quantum spin chains.

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I. Tsukada, Y. Sasago, K. Uchinokura, A. Zheludev, S. Maslov, G. Shirane, K. Kakurai, E. Ressouche. 1999-02-18. BaCu_2Si_2O_7: a new quasi 1-dimensional S = 1/2 antiferromagnetic chain system. https://arxiv.org/abs/cond-mat/9902251

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