O. I. Pat

O. Gamayun

C. Pascu Moca

Strong interactions reshape transport in one-dimensional quantum gases, with unusual temperature effects and anomalous current fluctuations.

A tractable framework is developed for strongly interacting multicomponent one-dimensional quantum gases, with transport through a junction treated as a local defect. The exact results reveal how interactions reshape particle and spin transport, producing linear low-temperature corrections, persistent oscillations from trapped states, and anomalous spin-current fluctuations not found in simple noninteracting systems.

We investigate the full counting statistics of a one-dimensional multicomponent impenetrable gas released from a bipartite state in the presence of a local defect. Spin--charge separation reduces the multivariate generating function to an exact Fredholm determinant whose kernel is built from time-evolved single-particle orbitals. Expressing these orbitals in terms of scattering data gives access to both transient dynamics and the nonequilibrium steady state. We derive the leading long-time asymptotics and identify persistent oscillations in densities and currents caused by multiple bound states at the junction. We argue that interactions between components lead to a linear low-temperature correction to the current, in contrast to the quadratic correction in the single-component case. At equilibrium, we obtain the M-Wright distribution of spin transfer with t1/4 scaling.

Nonequilibrium full counting statistics of multicomponent strongly-interacting quantum gases with defects