Year: 2026
Type: article
Abstract: Building on the Bethe ansatz and generalized hydrodynamics, we rigorously establish universal relations between Drude weights governing charge, spin, and heat transport and thermodynamic properties for the one-dimensional repulsive two-component continuum Fermi gas-the paradigmatic integrable Yang-Gaudin model. We analytically derive thermodynamic expressions for charge Drude weights: D nn , D nσ , D ne (responses of particle, magnetization and heat currents to a chemical potential gradient) equal the particle density, magnetization, and temperature times entropy density, respectively, per unit mass. These relations constitute a hallmark of ballistic transport, and can be generalized to other 1D continuum integrable systems. Furthermore, we investigate spin Drude weight ( D σσ , D σe ) at zero and low temperatures. They characterize the magnetization and heat current responses to a magnetic field gradient, revealing an essential spin-charge coupling feature in quantum transport. We find that the Drude weights D nσ , D σσ , and D σe across the μ-H plane remarkably map out the zero-temperature phase boundary. This work fills a critical gap in the understanding of transport within integrable quantum gases and furnishes a direct theoretical foundation for future ultracold-atom experiments.
Source: Chinese Physics Letters
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G6952626986, G7598817452, G8156642181
OpenAlex ID: W7221158670