• Media type: E-Article
  • Title: Reversal of quantized Hall drifts at noninteracting and interacting topological boundaries
  • Contributor: Zhu, Zijie; Gächter, Marius; Walter, Anne-Sophie; Viebahn, Konrad; Esslinger, Tilman
  • imprint: American Association for the Advancement of Science (AAAS), 2024
  • Published in: Science
  • Language: English
  • DOI: 10.1126/science.adg3848
  • ISSN: 0036-8075; 1095-9203
  • Origination:
  • Footnote:
  • Description: <jats:p> 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 <jats:italic>C</jats:italic> = +1 and another with <jats:italic>C</jats:italic> = –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. </jats:p>