Persistent currents in the two-chain correlated electron model

For the recently proposed exactly solvable two-chain correlated electron model with the anisotropic spin-spin interaction between electrons and the spin-orbit interaction the ground state persistent currents are calculated. The model describes the quasi-one-dimensional type II superconductor. It is shown, that the spin-orbit coupling determines the initial phase of oscillations of charge and spin persistent currents, related to unbound electron states. On the other hand, Cooper-like singlet pairs define oscillations of only charge persistent currents with the period, characteristic to pairs. Depending on the value of the external magnetic field and the band filling, the system can reveal the complicated picture of the interference of several kinds of oscillations. (author)