论文标题
YBMGGAO中均质旋转模型的重新研究$ _4 $
Reinvestigation of the homogeneous spin model in YbMgGaO$_4$
论文作者
论文摘要
由最近在$ \ mathrm {ybmggao} _4 $ \ cite {william2019}上进行的无弹性中子散射实验的动机，我们重新介绍了三角晶格上的同质自旋模型。使用簇平均场理论，我们研究了相图和磁场诱导的相变。我们发现条纹状态与$ 120^{\ Circ} $抗磁磁状态之间的相边界被磁场扩大，从而导致磁场诱导的相变。下一个最新的邻居交换交互$ j_2/j_1 $抑制了这种相变，并以$ j_2/j_1> 0.13 $消失。我们发现一个$ J_2/j_1 = 0.1 $的参数空间可以实现现场引导过渡，并且理论自旋激发能与实验数据的偏差仅为$ 5.4 \％\％$。我们的结果表明，有效的均匀旋转模型仍然可以在$ \ mathrm {ybmggao} _4 $中起作用。
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 $\mathrm{YbMgGaO}_4$.
