对YbMgGaO $_4$中均匀自旋模型的再研究
Reinvestigation of the homogeneous spin model in YbMgGaO$_4$
摘要：
受最近在$\mathrm{YbMgGaO}_4$ \cite{William2019}上进行的中子非弹性散射实验的启发，我们重新研究了三角晶格上的均匀自旋模型。利用集团平均场理论，我们研究了相图和磁场诱导相变。我们发现，条纹态和$120^{\circ}$反铁磁态之间的相界被磁场加宽，导致场诱导相变。这种相变被次近邻交换相互作用$J_2/J_1$抑制，并以$J_2/J_1>0.13$形式消失。我们在$J_2/J_1=0.1$上找到了一个参数空间，在这个参数空间中，自旋激发能的理论值与实验值的偏差仅为$5.4\%$。我们的结果表明，一个有效的均匀自旋模型仍然适用于$\mathrm{YbMgGaO}_4$。
英文摘要：
Motivated by a recent inelastic neutron scattering experiment on $\mathrm{YbMgGaO}_4$ \cite{William2019}, we reinvestigate the homogeneous spin model on the triangular lattice. Using the cluster mean-field theory, we study the phase diagram and the magnetic-field-induced phase transition. We find that the phase boundary between the stripe state and the $120^{\circ}$ antiferromagnetic state is broadened by the magnetic field, leading to a field-induced phase transition. This phase transition is suppressed by the next-nearest neighbor exchange interaction $J_2/J_1$ and vanishes as $J_2/J_1>0.13$. We find a parameter space at $J_2/J_1=0.1$, in which the field-induce transition can be achieved and the deviation of theoretical spin excitation energies from experimental data is only $5.4\%$. Our results imply that an effective homogeneous spin model still works in $\mathrm{YbMgGaO}_4$.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
