Identifying the elusive spinon excitations in quantum spin liquid (QSL) materials is what scientists have long sought for. Recently, thermal conductivity (κ) has emerged to be a decisive probe because the fermionic nature of spinons leads to a characteristic nonzero linear κ0/T term while approaching zero Kelvin. So far, only a few systems have been reported to exhibit such term. Here, we report a κ0/T≈ 0.01 WK−2m−1, the largest κ0/T value ever observed in magnetic oxide QSL candidates, in a new quantum magnet Pr2Ga2BeO7 with a Shastry-Sutherland lattice (SSL). Its QSL nature is further supported by the power-law temperature dependence of the specific heat, a plateau of muon spin relaxation rate, and gapless inelastic neutron spectra. Our theoretical analysis reveals that the introduction of XY spin anisotropy is the key for Pr2Ga2BeO7 to be the first QSL realized on the SSL, after more than four decades of extensive studies on this celebrated magnetically frustrated lattice.
@article{arxiv.2405.13628,
title = {Spinons in a new Shastry-Sutherland lattice magnet Pr$_2$Ga$_2$BeO$_7$},
author = {N. Li and A. Brassington and M. F. Shu and Y. Y. Wang and H. Liang and Q. J. Li and X. Zhao and P. J. Baker and H. Kikuchi and T. Masuda and G. Duan and C. Liu and H. Wang and W. Xie and R. Zhong and J. Ma and R. Yu and H. D. Zhou and X. F. Sun},
journal= {arXiv preprint arXiv:2405.13628},
year = {2024}
}
Comments
20 pages, 6 figures, with Supplementary Information