CuO2正方晶格的二维双孤子模型

采用较强的电声非线性相互作用作为电子配对机制,从氧化物高温超导材料的CuO₂面准二维特性出发,以实验观察到的CuO₂面上存在相当强的局域电声相互作用为基础,建立了一个二维双孤子理论模型,给出了具有拓扑稳定性的孤子解,双孤子的运动具有各向异性,且总是以低于声速的速度运动,因此它不辐射声子,即它的动力学能量不转变为热能,临界转变温度T_c与晶胞的质量无关,因而不存在同位素效应。

TWO-DIMENSIONAL BISOLITON MODEL IN CuO2 SQUARE CRYSTAL LATTICE

A moderately strong electron-phonon interaction is supposed to be the causes of paring. On the basis of (1) the observation that the local electron-phonon interaction is rather strong in experiment and (2) the quasi-two-dimensional feature of CuO₂ plane in ceramic oxides, a two-dimensional bisoli-ton model is established. The soliton solution with topological stability is given. It is shown that the bisoliton moves always with a velocity less than that of sound and it is varied along different direc-tions, they do not emit phonons, i.e., they do not transform their kinetic energy into a thermal one. The absence of an isotopic effect is explained because the critical temperature is independent of the mass of crystal lattice cell.