论文标题
honeycomb晶格的XY模型中的远程顺序
Long-range order in the XY model on the honeycomb lattice
论文作者
论文摘要
使用反射阳性方法，我们提供了严格的证明，证明了XY模型在大型旋转$ s \ ge 2 $的honeycomb晶格上存在远程磁性顺序。这与使用{\ it Same}方法获得的结果相反，但在平方晶格上 - 为Spins $ S \ ge 1 $提供了稳定的长距离顺序。 We suggest that the difference between these two cases stems from the enhanced quantum spin fluctuations on the honeycomb lattice.使用线性自旋理论，我们表明，增强的波动是由于蜂窝晶格上自旋波的总体动能（带有dirac点）要比方格（具有良好的嵌套特性）高得多。
Using the reflection positivity method we provide the rigorous proof of the existence of long range magnetic order for the XY model on the honeycomb lattice for large spins $S\ge 2$. This stays in contrast with the result obtained using the {\it same} method but on the square lattice -- which gives a stable long-range order for spins $S\ge 1$. We suggest that the difference between these two cases stems from the enhanced quantum spin fluctuations on the honeycomb lattice. Using linear spin-wave theory we show that the enhanced fluctuations are due to the overall much higher kinetic energy of the spin waves on the honeycomb lattice (with Dirac points) than on the square lattice (with good nesting properties).
