Charge kinks are considered as fundamental excitations in quarter-filled charge-ordered ladders. The strength of the coupling of the kinks to the three-dimensional lattice depends on their energy. The integrated intensity of Raman scattering by kink-antikink pairs is proportional to $phi ^{5}$ or $phi ^{4},$ where $phi $ is the order parameter. The exponent is determined by the system parameters and by the strength of the electron-phonon coupling.
Download