Charge Excitation Dynamics in Bosonic Fractional Chern Insulators

Area of Science:

• Condensed Matter Physics
• Quantum Gases
• Topological Matter

Background:

• Ultracold atomic gases provide a platform for realizing topological states of matter.
• Fractional Chern insulator (FCI) states are predicted in the Harper-Hofstadter model at half-filling with strong interactions.
• The out-of-equilibrium dynamics of FCI states remain largely unexplored.

Purpose of the Study:

• Investigate the response of the FCI state to localized perturbations.
• Characterize the edge dynamics of the topological state under non-equilibrium conditions.
• Compare the dynamics with single-particle models.

Main Methods:

• Density matrix renormalization group (DMRG) simulations.
• Analysis of edge dynamics following localized perturbations.
• Confirmation of static properties of the FCI phase.

Main Results:

• Gapless edge features of the FCI state are observable in dynamics.
• Local edge perturbations propagate chirally, independent of perturbation strength.
• Density leakage from edge to bulk occurs, challenging simple Luttinger theory interpretations.

Conclusions:

• The study provides insights into the non-equilibrium dynamics of FCI states in ultracold atomic gases.
• Chiral edge dynamics in FCI states exhibit distinct behavior compared to non-interacting models.
• Observed density leakage necessitates refined theoretical models for FCI dynamics.