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Geometric Frustration and Dimensional Reduction at a Quantum Critical Point

C. D. Batista·J. Schmalian·N. Kawashima·P. Sengupta·S. E. Sebastian·N. Harrison·M. Jaime·I. R. Fisher
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Abstract

We show that the spatial dimensionality of the quantum critical point associated with Bose--Einstein condensation at T=0 is reduced when the underlying lattice comprises a set of layers coupled by a frustrating interaction. Our theoretical predictions for the critical temperature as a function of the chemical potential correspond very well with recent measurements in BaCuSi$_{2}$O$_{6}$ [S. E. Sebastian \textit{et al}, Nature \textbf{411}, 617 (2006)].

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C. D. Batista, J. Schmalian, N. Kawashima, P. Sengupta, S. E. Sebastian, N. Harrison, M. Jaime, I. R. Fisher. 2007-04-27. Geometric Frustration and Dimensional Reduction at a Quantum Critical Point. https://doi.org/10.1103/physrevlett.98.257201

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