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arXiv · 2406.15314

A Candidate for the Quantum Spin Liquid Ground-State in the Shastry-Sutherland Lattice Material Yb$_2$Be$_2$GeO$_7$

M. Pula·S. Sharma·J. Gautreau·Sajilesh K. P.·A. Kanigel·M. D. Frontzek·T. N. Dolling·L. Clark·S. Dunsiger·A. Ghara·G. M. Luke
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Abstract

The quasi-2D Shastry-Sutherland model has remained topical in the field of condensed matter physics for the last two decades, following the experimental realization of the model in the material SrCu$_2$(BO$_3$)$_2$. Since then, research into the Shastry-Sutherland system has revealed more nuanced physics than initially predicted; recent theoretical works have even predicted a quantum spin liquid phase may exist. Herein, we report on a new Shastry-Sutherland lattice material, Yb$_2$Be$_2$GeO$_7$, of the rare-earth melilite family RE$_2$Be$_2$GeO$_7$. We find, through SQUID magnetometry, powder neutron diffraction, specific heat capacity, and muon spin relaxation, that Yb$_2$Be$_2$GeO$_7$ lacks magnetic order and exhibits persistent spin dynamics to at least 17 mK. We propose the Shastry-Sutherland lattice material Yb$_2$Be$_2$GeO$_7$ as a candidate to host a quantum spin liquid ground-state.

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M. Pula, S. Sharma, J. Gautreau, Sajilesh K. P., A. Kanigel, M. D. Frontzek, T. N. Dolling, L. Clark, S. Dunsiger, A. Ghara, G. M. Luke. 2024-06-21. A Candidate for the Quantum Spin Liquid Ground-State in the Shastry-Sutherland Lattice Material Yb$_2$Be$_2$GeO$_7$. https://doi.org/10.1103/physrevb.110.014412

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