Effects of electron-spin exchange interaction on the electronic state of the one-dimensional spin-electron-phonon system

A one-dimensional spin-electron-phonon model is proposed for the discovery of new compounds composed of strongly correlated electrons. The total energies and the energy gaps at half filling and less-than half-filling have been computed within a mean-field theory and a periodic boundary condition. As the value of the antiferromagnetic (AF) exchange interaction between nearest-neighbor itinerant-electron spin and localized spin is increased, the energy gaps of 0 and two holes increase and the binding energy of two holes increases. This system with two holes formates a bound state. It turns out that the AF exchange interaction between itinerant-electron spin and localized spin plays the important role in the electronic state of this system.