论文标题
在热力学极限中可集成扭曲的J1-J2自旋链中的基本激发
Elementary excitations in an integrable twisted J1-J2 spin chain in the thermodynamic limit
论文作者
论文摘要
研究了典型的U（1）对称性破碎量子积分系统中的确切基本激发，即与最近邻居，下一个最近的邻居和手性的三个自旋相互作用的扭曲的J1-J2自旋链。主要技术是，我们通过转移矩阵的零根来量化系统的能量光谱，而不是传统的伯特根。从数值计算和奇异性分析中，我们获得了零根的模式。基于它们，我们通过分析获得基态能量和热力学极限中的基本激发。我们发现，该系统还表现出$η\ in \ Mathbb {r} $的政权中几乎退化的状态，Z方向上最近的邻居耦合是铁磁。更仔细的研究表明，相互作用的竞争可以引起无间隙的低覆盖激发和量子相变的抗铁磁状态，并以$η\ in \ Mathbb {r}+iπ$中的$η\。
The exact elementary excitations in a typical U(1) symmetry broken quantum integrable system, that is the twisted J1-J2 spin chain with nearest-neighbor, next nearest neighbor and chiral three spin interactions, are studied. The main technique is that we quantify the energy spectrum of the system by the zero roots of transfer matrix instead of the traditional Bethe roots. From the numerical calculation and singularity analysis, we obtain the patterns of zero roots. Based on them, we analytically obtain the ground state energy and the elementary excitations in the thermodynamic limit. We find that the system also exhibits the nearly degenerate states in the regime of $η\in \mathbb{R}$, where the nearest-neighbor couplings among the z-direction are ferromagnetic. More careful study shows that the competing of interactions can induce the gapless low-lying excitations and quantum phase transition in the antiferromagnetic regime with $η\in \mathbb{R}+iπ$.
