Agrawal Utkarsh, Gopalakrishnan Sarang, Vasseur Romain
Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Department of Physics and Astronomy, CUNY College of Staten Island, Staten Island, New York 10314; Physics Program and Initiative for the Theoretical Sciences, The Graduate Center, City University of New York, New York, New York 10016, USA.
Phys Rev Lett. 2020 Dec 31;125(26):265702. doi: 10.1103/PhysRevLett.125.265702.
Quantum critical points in quasiperiodic magnets can realize new universality classes, with critical properties distinct from those of clean or disordered systems. Here, we study quantum phase transitions separating ferromagnetic and paramagnetic phases in the quasiperiodic q-state Potts model in 2+1D. Using a controlled real-space renormalization group approach, we find that the critical behavior is largely independent of q, and is controlled by an infinite-quasiperiodicity fixed point. The correlation length exponent is found to be ν=1, saturating a modified version of the Harris-Luck criterion.
准周期磁体中的量子临界点可以实现新的普适类，其临界性质不同于纯净或无序系统。在此，我们研究二维加一维准周期q态Potts模型中分隔铁磁相和顺磁相的量子相变。使用可控的实空间重整化群方法，我们发现临界行为在很大程度上与q无关，且由一个无限准周期不动点控制。相关长度指数被发现为ν = 1，满足哈里斯-勒克判据的一个修正版本。
