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Role of anisotropy in the spin-dimer compound BaCuSi2O6

Suchitra E. Sebastian·P. Tanedo·P. A. Goddard·S. -C. Lee·A. Wilson·S. Kim·S. Cox·R. D. McDonald·S. Hill·N. Harrison·C. D. Batista·I. R. Fisher
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Abstract

We present results of magnetisation and electron paramagnetic resonance experiments on the spin-dimer system BaCuSi2O6. Evidence indicates that the origin of anisotropic terms in the spin Hamiltonian is from magnetic dipolar interactions. Axial symmetry-breaking is on a very small energy scale of ~11 mK, confirming Bose Einstein condensation critical scaling over an extended temperature range in the vicinity of the quantum critical point.

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Suchitra E. Sebastian, P. Tanedo, P. A. Goddard, S. -C. Lee, A. Wilson, S. Kim, S. Cox, R. D. McDonald, S. Hill, N. Harrison, C. D. Batista, I. R. Fisher. 2006-10-28. Role of anisotropy in the spin-dimer compound BaCuSi2O6. https://doi.org/10.1103/physrevb.74.180401

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