Three-Leg Antiferromagnetic Heisenberg Ladder with Frustrated Boundary Condition; Ground State Properties
Three-Leg Antiferromagnetic Heisenberg Ladder with Frustrated Boundary Condition; Ground State Properties
复制标题
受挫边界条件三腿反铁磁海森堡梯；
DOI：
10.1143/jpsj.66.4001
复制
发表时间：
1997
影响因子：
1.7
通讯作者：
Minoru Takahashi
中科院分区：
文献类型：
--
作者：
K. Kawano;Minoru Takahashi
研究了三腿阶梯上的反铁磁性海森堡自旋系统。在横档方向上施加周期性边界条件。对于所有反铁磁链间耦合(J⊥>；0)，该系统都有一个激发间隙。强耦合极限(J⊥/J1→∞)的估计间隙为0.28J1。尽管相互作用是均匀的，只有最近邻相互作用，但系统的基态是二聚化的，打破了热力学极限下的平移对称性。引入次近邻耦合(J2)，我们可以看到系统的精确解。基态波函数是完全二聚体有序的。利用密度矩阵重正化群算法，数值证明了原模型(J2=0)与精确可解模型具有相同的性质。讨论了具有较高奇数支数的梯形波的基态性质。
The antiferromagnetic Heisenberg spin systems on the three-leg ladder are investigated. Periodic boundary condition is imposed in the rung direction. The system has an excitation gap for all antiferromagnetic inter-chain coupling ( J ⊥ >0). The estimated gap for the strong coupling limit ( J ⊥ / J 1 →∞) is 0.28 J 1 . Although the interaction is homogeneous and only nearest-neighbor, the ground states of the system are dimerized and break the translational symmetry in the thermodynamic limit. Introducing the next-nearest neighbor coupling ( J 2 ), we can see that the system is solved exactly. The ground state wave function is completely dimer-ordered. Using density matrix renomalization group algorithm, we show numerically that the original model ( J 2 =0) has the same nature with the exactly solvable model. The ground state properties of the ladder with a higher odd number of legs are also discussed.