Kim Isaac H, Shi Bowen, Kato Kohtaro, Albert Victor V
Department of Computer Science, University of California, Davis, Davis 95616, California, USA.
Centre for Engineered Quantum Systems, School of Physics, University of Sydney, Sydney 2043, NSW, Australia.
Phys Rev Lett. 2022 Apr 29;128(17):176402. doi: 10.1103/PhysRevLett.128.176402.
A (2+1)-dimensional gapped quantum many-body system can have a topologically protected energy current at its edge. The magnitude of this current is determined entirely by the temperature and the chiral central charge, a quantity associated with the effective field theory of the edge. We derive a formula for the chiral central charge that, akin to the topological entanglement entropy, is completely determined by the many-body ground state wave function in the bulk. According to our formula, nonzero chiral central charge gives rise to a topological obstruction that prevents the ground state wave function from being real valued in any local product basis.
一个（2 + 1）维带隙量子多体系统在其边缘可以有一个拓扑保护的能量流。该电流的大小完全由温度和手征中心荷决定，手征中心荷是一个与边缘有效场论相关的量。我们推导出一个手征中心荷的公式，类似于拓扑纠缠熵，它完全由体中的多体基态波函数决定。根据我们的公式，非零的手征中心荷会产生一个拓扑障碍，阻止基态波函数在任何局域乘积基中取实值。
