Journal of Physics A Mathematical and General
Multi-particle scattering at the same position in the Bethe ansatz for two-band electrons with spin-exchange interaction
Zu‐Jian Ying, You‐Quan Li, Shi-Jian Gu
Abstract
The same-position scattering (SPS) of more than two electrons in a one-dimensional model of two-band electrons with spin-exchange interaction is discussed. The boundary conditions of three- and four-particle SPS are given. It is shown that the conditions can be fulfilled by the two-particle boundary conditions for the Bethe ansatz (BA) wavefunction. Consequently, the definition of the BA wavefunction can be extended to those cases of more than two particles occupying the same position. Therefore, unlike the case in lattice models in which configurations with more than two particles at one site are excluded in applying the approach, the BA is valid without the exclusion of multi-particle SPS in the spin-exchange model. A relation between the SU (2) × SU (2) symmetry and the BA equation is also indicated.