Reversal of quantised Hall drifts at non-interacting and interacting topological boundaries

Abstract

The transport properties of gapless edge modes at boundaries between topologically distinct domains are of fundamental and technological importance. Therefore, it is crucial to gain a better understanding of topological edge states and their response to interparticle interactions. Here, we experimentally study long-distance quantised Hall drifts in a harmonically confined topological pump of non-interacting and interacting ultracold fermionic atoms. We find that quantised 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 corresponds to a band transfer between a band with Chern number $C=+1$ and a band with $C=-1$ via a gapless edge mode, in agreement with the bulk-edge correspondence for non-interacting particles. We establish that a non-zero repulsive Hubbard interaction leads to the emergence of an additional edge in the system, relying on a purely interaction-induced mechanism, in which pairs of fermions are split.

References in corpus (35)

• Topological Insulators
• Topological Photonics
• Experimental realisation of the topological Haldane model
• Imaging topological edge states in silicon photonics
• Topological States and Adiabatic Pumping in Quasicrystals
• Direct Measurement of the Zak phase in Topological Bloch Bands
• Measuring the Chern number of Hofstadter bands with ultracold bosonic atoms
• Floquet Engineering of Quantum Materials
• Topological Bands for Ultracold Atoms
• Observation of chiral edge states with neutral fermions in synthetic Hall ribbons
• A Thouless Quantum Pump with Ultracold Bosonic Atoms in an Optical Superlattice
• Topological Thouless Pumping of Ultracold Fermions
• Visualizing edge states with an atomic Bose gas in the quantum Hall regime
• Observation of the topological soliton state in the Su-Schrieffer-Heeger model
• Mapping topological order in coordinate space
• Topological charge pumping in a one-dimensional optical lattice
• Thouless pumping and topology
• Direct observation of chiral currents and magnetic reflection in atomic flux lattices
• Artificial graphene with tunable interactions
• Probing chiral edge dynamics and bulk topology of a synthetic Hall system
• Topological states in two-dimensional optical lattices
• Real-space imaging of a topological protected edge state with ultracold atoms in an amplitude-chirped optical lattice
• Competition and interplay between topology and quasi-periodic disorder in Thouless pumping of ultracold atoms
• Quantisation and its breakdown in a Hubbard-Thouless pump
• Effects of Smooth Boundaries on Topological Edge Modes in Optical Lattices
• Phase diagram of the Hubbard chain with two atoms per cell
• Quantum Transport of Bosonic Cold Atoms in Double Well Optical Lattices
• Topological pumping in a Floquet-Bloch band
• Simulating Chern insulators on a superconducting quantum processor
• Splitting of topological charge pumping in an interacting two-component fermionic Rice-Mele Hubbard model
• Creating topological interfaces and detecting chiral edge modes in a 2D optical lattice
• Interacting Hofstadter Interface
• Non-diffracting states in one-dimensional Floquet photonic topological insulators
• Quantum particle in a parabolic lattice in the presence of a gauge field
• Growing quantum states with topological order

Cited by in corpus (11)

• Interactions enable Thouless pumping in a nonsliding lattice
• Thouless pumping and trapping of two-component gap solitons
• Quantized Hall drift in a frequency-encoded photonic Chern insulator
• Chiral polaron formation on the edge of topological quantum matter
• Splitting and connecting singlets in atomic quantum circuits
• Topological photon pumping in quantum optical systems
• Reentrant topology and reverse pumping in a quasiperiodic flux ladder
• Galilei covariance of the theory of Thouless pumps
• Ultracold atomic lattice systems for simulating topological phases: A review
• Dark solitons in nonlinear Su-Schrieffer-Heeger lattices
• Optical control of electrons in a Floquet topological insulator