Transport and Entanglement across Integrable Impurities from Generalized Hydrodynamics

Area of Science:

• Condensed Matter Physics
• Quantum Mechanics
• Statistical Physics

Background:

• Quantum impurity models (QIMs) are fundamental in physics, simplifying complex systems and describing experimental platforms.
• While equilibrium QIMs are well-understood, their nonequilibrium dynamics remain largely unexplored.
• Recent advances in generalized hydrodynamics (GHD) for integrable systems offer a new avenue for studying QIMs.

Purpose of the Study:

• To extend the generalized hydrodynamics (GHD) framework to include integrable interacting quantum impurity models (QIMs).
• To develop a theoretical approach for understanding the nonequilibrium behavior of QIMs, particularly focusing on impurity scattering effects.

Main Methods:

• Development of Bethe-Boltzmann type equations tailored for interacting QIMs, incorporating impurity scattering.
• Application of the extended GHD framework to analyze a bipartitioning quench scenario.
• Derivation of expressions for entanglement entropy and full counting statistics.

Main Results:

• Introduction of impurity GHD equations that account for impurity scattering and entropy production.
• Analysis of density and current profiles in a bipartitioning quench with a backscattering impurity.
• Quantification of the impact of impurity strength on system dynamics.

Conclusions:

• The study successfully extends GHD to a broader class of quantum impurity models, enhancing our understanding of their nonequilibrium physics.
• The developed Bethe-Boltzmann equations provide a powerful tool for investigating impurity scattering and related phenomena.
• The findings pave the way for future research into complex quantum many-body systems out of equilibrium.