Iemini Fernando, Mora Christophe, Mazza Leonardo
ICTP, Strada Costiera 11, I-34151 Trieste, Italy.
NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56126 Pisa, Italy.
Phys Rev Lett. 2017 Apr 28;118(17):170402. doi: 10.1103/PhysRevLett.118.170402. Epub 2017 Apr 25.
Parafermions are emergent excitations that generalize Majorana fermions and can also realize topological order. In this Letter, we present a nontrivial and quasi-exactly-solvable model for a chain of parafermions in a topological phase. We compute and characterize the ground-state wave functions, which are matrix-product states and have a particularly elegant interpretation in terms of Fock parafermions, reflecting the factorized nature of the ground states. Using these wave functions, we demonstrate analytically several signatures of topological order. Our study provides a starting point for the nonapproximate study of topological one-dimensional parafermionic chains with spatial inversion and time-reversal symmetry in the absence of strong edge modes.
准费米子是一种推广了马约拉纳费米子的涌现激发，并且还能实现拓扑序。在本信函中，我们给出了一个处于拓扑相的准费米子链的非平凡且近似可精确求解的模型。我们计算并刻画了基态波函数，它们是矩阵乘积态，并且在用福克准费米子表示时有特别优美的解释，这反映了基态的因式分解性质。利用这些波函数，我们通过解析方法证明了拓扑序的几个特征。我们的研究为在没有强边缘模式的情况下对具有空间反演和时间反演对称性的一维拓扑准费米子链进行非近似研究提供了一个起点。
