近日，瑞士苏黎世联邦理工学院Konrad Viebahn及其研究团队取得一项新进展。经过不懈努力，他们对非相互作用和相互作用拓扑边界处量子化霍尔漂移的逆转进行了研究
该研究团队通过实验深入研究了，超冷费米子原子在谐波约束拓扑泵中的远距离量子化霍尔漂移现象。研究人员发现，当原子接近约束势的临界斜率时，量子化漂移会停止并发生方向逆转，这一现象揭示了拓扑边界的存在。
这种漂移逆转与两个不同陈数（C = +1和C = -1）的能带之间，通过无能隙边缘模式的能带转移密切相关，这与非相互作用粒子的体边对应关系一致。此外，非零排斥性哈伯德相互作用通过费米子对分裂的机制，在系统中诱导了额外边缘的出现。
据悉，在拓扑结构不同域之间的边界处，无间隙边缘模式的输运性质具有重要的基础和技术意义。
附：英文原文
Title: Reversal of quantized Hall drifts at noninteracting and interacting topological boundaries
Author: Zijie Zhu, Marius Gchter, Anne-Sophie Walter, Konrad Viebahn, Tilman Esslinger
Issue&Volume: 2024-04-19
Abstract: The transport properties of gapless edge modes at boundaries between topologically distinct domains are of fundamental and technological importance. We experimentally studied long-distance quantized Hall drifts in a harmonically confined topological pump of ultracold fermionic atoms. We found that quantized drifts halt and reverse their direction when the atoms reach a critical slope of the confining potential, revealing the presence of a topological boundary. The drift reversal corresponded to a band transfer between a band with Chern number C = +1 and another with C = –1 through a gapless edge mode, in agreement with the bulk-edge correspondence for noninteracting particles. Nonzero repulsive Hubbard interactions led to the emergence of an additional edge in the system through a mechanism in which pairs of fermions are split.
Source: https://www.science.org/doi/10.1126/science.adg3848