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arXiv · 2001.08219

On two phases inside the Bose condensation dome of Yb$_2$Si$_2$O$_7$

Michael O. Flynn·Thomas E. Baker·Siddharth Jindal·Rajiv R. P. Singh
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Abstract

Recent experimental data on Bose-Einstein Condensation (BEC) of magnons in the spin-gap compound Yb$_2$Si$_2$O$_7$ revealed an asymmetric BEC dome arXiv:1810.13096v2. We examine modifications to the Heisenberg model on a breathing honeycomb lattice, showing that this physics can be explained by competing forms of weak anisotropy. We employ a gamut of analytical and numerical techniques to show that the anisotropy yields a field driven phase transition from a state with broken Ising symmetry to a phase which breaks no symmetries and crosses over to the polarized limit.

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Michael O. Flynn, Thomas E. Baker, Siddharth Jindal, Rajiv R. P. Singh. 2020-01-22. On two phases inside the Bose condensation dome of Yb$_2$Si$_2$O$_7$. https://doi.org/10.1103/physrevlett.126.067201

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