论文标题
检测量子关键时出现的连续对称性
Detecting emergent continuous symmetries at quantum criticality
论文作者
论文摘要
如果在重新归一化群体下，在哈密顿量中的对称性破坏术语是无关紧要的，则可以在不具有对称性的哈密顿量的低能频谱上出现新的或增大的对称性。在这封信中，我们提出了一种基于张量的网络算法来从任何量子旋转链的基态上提取晶格操作员对晶格操作员的近似，而无需先验了解其低能的有效田间理论。我们对Spin-1/2 $ J $ -Q $ HEISENBERG链的结果以及一个脱合的量子关键点（DQCP）的一维版本展示了我们方法获得新兴晶格Kac-Moody发电机的功能。它也可以看作是找到可集成模型的本地运动积分和关键无间隙基态的本地父母哈密顿量的一种方式。
New or enlarged symmetries can emerge at the low-energy spectrum of a Hamiltonian that does not possess the symmetries, if the symmetry breaking terms in the Hamiltonian are irrelevant under the renormalization group flow. In this letter, we propose a tensor network based algorithm to numerically extract lattice operator approximation of the emergent conserved currents from the ground state of any quantum spin chains, without the necessity to have prior knowledge about its low-energy effective field theory. Our results for the spin-1/2 $J$-$Q$ Heisenberg chain and a one-dimensional version of the deconfined quantum critical points (DQCP) demonstrate the power of our method to obtain the emergent lattice Kac-Moody generators. It can also be viewed as a way to find the local integrals of motion of an integrable model and the local parent Hamiltonian of a critical gapless ground state.
