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Theory of spin density profile in the magnetization plateaus of SrCu_2(BO_3)_2

Shin Miyahara·Federico Becca·Frederic Mila
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Abstract

The two-dimensional spin-gap system ${\rm SrCu_2(BO_3)_2}$ shows unique physical properties due to the low-dimensionality character and the strong quantum fluctuations. Experimentally, 1/8-, 1/4-, and 1/3-plateaus have been observed in the magnetization curve under magnetic fields up to 70 Tesla, and the 1/2-plateau is expected to be stabilized at higher magnetic fields. We argue that spin-lattice effects are necessary to describe the superstructures at the plateaus, and we propose a simple microscopic model of spins interacting adiabatically with the lattice to reproduce the main features of the recent experimental results by nuclear magnetic resonance.

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Shin Miyahara, Federico Becca, Frederic Mila. 2003-02-17. Theory of spin density profile in the magnetization plateaus of SrCu_2(BO_3)_2. https://doi.org/10.1103/physrevb.68.024401

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