Deng Zehui, Liu Lu, Guo Wenan, Lin Hai-Qing
<a href="https://ror.org/04tavf782">Beijing Computational Science Research Center</a>, Beijing 100193, China.
School of Physics, <a href="https://ror.org/01skt4w74">Beijing Institute of Technology</a>, Beijing 100081, China.
Phys Rev Lett. 2024 Sep 6;133(10):100402. doi: 10.1103/PhysRevLett.133.100402.
We study the scaling behavior of the Rényi entanglement entropy with smooth boundaries at the putative deconfined critical point separating the Néel antiferromagnetic and valence-bond-solid states of the two-dimensional J-Q_{3} model. We observe a subleading logarithmic term with a coefficient indicating the presence of four Goldstone modes, signifying the presence of an SO(5) symmetry at the transition point, which spontaneously breaks into an O(4) symmetry in the thermodynamic limit. This result supports the conjecture that an SO(5) symmetry emerges at the transition point, but reveals the transition to be weakly first-order. We demonstrate, through this Letter, a novel approach to detect emergent continuous symmetry and, more importantly, identify weakly first-order phase transitions efficiently, which have been notoriously challenging for conventional methods.
我们研究了在二维(J-Q_{3})模型中，分隔奈尔反铁磁态和价键固态的假定去禁闭临界点处具有光滑边界的雷尼纠缠熵的标度行为。我们观察到一个次主导对数项，其系数表明存在四个戈德斯通模式，这意味着在转变点存在(SO(5))对称性，该对称性在热力学极限下自发破缺为(O(4))对称性。这一结果支持了在转变点出现(SO(5))对称性的猜想，但揭示了该转变是弱一级的。通过这封信，我们展示了一种检测涌现连续对称性的新方法，更重要的是，能够有效地识别弱一级相变，而这对于传统方法来说一直是极具挑战性的。
