Topic: 1D repulsive Hubbard model: From quantum liquid to transport

Speaker: Prof. Xi-Wen Guan

Coordinates: Classroom 5204, 16:00, Tuesday, April 23

Abstract: The Hubbard model, although extensively studied for a long time, has found renewed interest and become increasingly important in condensed matter physics, ultracold atoms and quantum metrology. In this talk, we will present new results of one-dimensional repulsive Hubbard model in the presence of a magnetic field.  Using Bethe ansatz solution, we rigorously show that the fractional spin and holon excitations display different features of spin-charge separation in various phases regimes. We determine universal behavior of such spin-coherent and -incoherent liquids, Tan’s contact and the interaction-driven criticality in and near different phases. In particular, analytical and general results on spin and charge Drude weights are obtained for the ground state, the Luttinger liquid and the quantum critical region at both zero and finite temperatures, showing deep insights into ballistic,  diffusive quantum transports and interplay between spin and charge  in the model.