论文标题
Neel和Valence Bond固体相之间的连续相变
Continuous phase transition between Neel and valence bond solid phases in a J-Q-like spin ladder system
论文作者
论文摘要
我们研究了Neel相和价键固体（VBS）相之间的量子相变，在每个Z2对称性中，在Spin-1/2两腿XXZ梯子中都损坏了不同的Z2对称性，并具有四旋链相互作用。该模型可以被视为在方格上著名的J-Q模型的一维变体。通过变异统一矩阵乘积计算和有效的场理论，我们确定了模型的相图，并证明了Neel-VBS转变是连续的，并且属于中央电荷C = 1的高斯通用类别。特别是，发现关键指数$β，η，$和$ν$可以满足数值准确性内高斯过渡期望的约束。这些指数通常不会在相边界上进行检测到，而对于高斯类，它们通常可以这样做。
We investigate a quantum phase transition between a Neel phase and a valence bond solid (VBS) phase, in each of which a different Z2 symmetry is broken, in a spin-1/2 two-leg XXZ ladder with a four-spin interaction. The model can be viewed as a one-dimensional variant of the celebrated J-Q model on a square lattice. By means of variational uniform matrix product state calculations and an effective field theory, we determine the phase diagram of the model, and present evidences that the Neel-VBS transition is continuous and belongs to the Gaussian universality class with the central charge c=1. In particular, the critical exponents $β, η,$ and, $ν$ are found to satisfy the constraints expected for a Gaussian transition within numerical accuracy. These exponents do not detectably change along the phase boundary while they are in general allowed to do so for the Gaussian class.
