论文标题
U（1） - 对称受保护的dirac节点循环SRCU2（BO3）2
U(1)-Symmetry protected Dirac nodal loops of triplons in SrCu2(BO3)2
论文作者
论文摘要
我们在低对称阶段的几何沮丧的量子磁铁SRCU2（BO3）2的现实微观模型的低能微观模型中证明了对称性受保护的三位dirac模态线的外观。允许对称的dzyaloshinskii-moriya相互作用在粘结器形式主义中诱导分散性三角形带，该形式在布里渊区的扩展封闭路径上线性交叉。我们的结果表明，节点线受到$ u（1）$对称性的保护，并且可靠地抵抗保留这种对称性的扰动。在存在纵向场的情况下，节点环会收缩和消失，从而消失了足够强的场。
We demonstrate the appearance of symmetry protected triplon Dirac modal lines in the low energy excitation spectrum of a realistic microscopic model of the geometrically frustrated quantum magnet SrCu2(BO3)2 in its high symmetry phase. The symmetry-allowed Dzyaloshinskii-Moriya interactions induce dispersive trilpon bands within the bond-operator formalism that cross linearly over an extended closed path in the Brillouin zone. Our results establish that the nodal lines are protected by a $U(1)$-symmetry and robust against perturbations that preserve this symmetry. In the presence of a longitudinal field, the nodal loop shrinks and vanishes for a sufficiently strong field.
