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Exact Demonstration of Magnetization Pleateaus and First Order Dimer-Néel Phase Transitions in a Modified Shastry-Sutherland Model for SrCu$_2$(BO$_3$)$_2$

Erwin Müller-Hartmann·Rajiv R. P. Singh·Christian Knetter·Götz S. Uhrig
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Abstract

We study a generalized Shastry-Sutherland model for the material SrCu$_2$(BO$_3$)$_2$. Along a line in the parameter space, we can show rigorously that the model has a first order phase transition between Dimerized and Néel-ordered ground states. Furthermore, when a magnetic field is applied in the Dimerized phase, magnetization plateaus develop at commensurate values of the magnetization. We also discuss various aspects of the phase diagram and properties of this model away from this exactly soluble line, which include gap-closing continuous transitions between Dimerized and magnetically ordered phases.

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Erwin Müller-Hartmann, Rajiv R. P. Singh, Christian Knetter, Götz S. Uhrig. 1999-10-12. Exact Demonstration of Magnetization Pleateaus and First Order Dimer-Néel Phase Transitions in a Modified Shastry-Sutherland Model for SrCu$_2$(BO$_3$)$_2$. https://doi.org/10.1103/physrevlett.84.1808

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