论文标题
s = 1/2中量子相变的现场取向依赖性，三角形矩阵抗fiferromagnet ba $ _3 $ cosb $ _2 $ o $ $ _9 $
Field-orientation dependence of quantum phase transitions in the S=1/2 triangular-lattice antiferromagnet Ba$_3$CoSb$_2$O$_9$
论文作者
论文摘要
ba $ _3 $ cosb $ _2 $ o $ _9 $近似于二维旋转1/2三角形的海森伯格抗fiferromagnet。该化合物显示磁场诱导的量子相变（包括1/3-Magnetization-Plateau），但由于磁场$ H $平行且垂直于$ c $轴的磁化过程由于弱易于平面各向异性和弱的易于的抗互层抗Fifferromagagnetic Explactaction而有所不同。为了阐明这两个场方向之间的量子相变量如何变化，我们使用脉冲高磁场测量了ba $ _3 $ cosb $ _2 $ _9 $中磁化过程的场角依赖性。我们将获得的磁场场角相图比较了通过大小簇平均方法与缩放方案和半经典理论相结合的磁场视野角相图。我们还发现了一个狭窄的1/3磁化平台和一个高场过渡，其磁化强度跳跃，以$ h \，{\ parallel} \，c $，在先前的研究中未观察到。
Ba$_3$CoSb$_2$O$_9$ approximates the two-dimensional spin-1/2 triangular-lattice Heisenberg antiferromagnet. This compound displays magnetic-field-induced quantum phase transitions, including the 1/3-magnetization-plateau, but its magnetization processes for the magnetic field $H$ parallel and perpendicular to the $c$ axis are different due to the weak easy-plane anisotropy and the weak interlayer antiferromagnetic exchange interaction. To elucidate how the quantum phase transitions change between these two field directions, we measured the field-angle dependence of the magnetization process in Ba$_3$CoSb$_2$O$_9$ using pulsed high magnetic fields. We compared obtained magnetic field-field angle phase diagram with those obtained by the large-size cluster mean-field method combined with a scaling scheme and the semiclassical theory. We also found a narrow 1/3-magnetization plateau and a high-field transition with a small magnetization jump for $H\,{\parallel}\,c$, not observed in the previous studies.
