arXiv:0908.1894 · Physical Review B
Susceptibility at the edge points of magnetization plateau of one-dimensional electron and spin systems
T. Vekua
Abstract
We study the behavior of magnetization curve as a function of magnetic field in the immediate vicinity of the magnetization plateaus of one-dimensional (1D) electron systems within the bosonization formalism. First we discuss the plateau that is formed at the saturation magnetization of 1D electron system. We treat interactions between electrons in the lowest order of perturbation. We show that for isolated systems, where total number of electrons is not allowed to vary, magnetic susceptibility stays always finite away of half filling. Similar statement holds for many other magnetization plateaus supporting nonmagnetic gapless excitations encountered in 1D electron/spin systems in the absence of special symmetries or features responsible for the mode decoupling. We demonstrate it on example of the plateaus at irrational values of magnetization in doped modulated Hubbard chains. Finally we discuss the connection between the weak coupling description of saturation magnetization plateau and strong coupling description of zero magnetization plateau of attractively interacting electrons.