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基于一维分子晶体系统的Holstein模型,采用压缩-相干态展开方法,计及电子-声子间量子关联和重整化平移修正,分析和研究电子-双声子相互作用对极化子-孤子系统基态性质和量子涨落的影响.推导了一维极化子-孤子系统的封闭形式非线性方程.应用非线性项展开方法,给出非线性方程的解析解和相关基态特性结果.研究表明,仅当电子-双声子耦合强度g1<0时非线性方程才有孤波解,此时声子量子涨落效应随着压缩的增加,极化子-孤子系统基态能量变得更负,孤子局域减少,孤子态更加稳定;另一方面,电子密度涨落〈Δ2n〉和声子坐标-动量的不确定量〈Δ2p〉〈Δ2q〉比无声子压缩效应的大,极化子结合能变得更负.特别是,当g1<0时,双声子效应的量子涨落〈Δ2n〉与〈Δ2p〉〈Δ2q〉的值比单声子情况有明显增加.
Based on the Holstein model of a one-dimensional molecular crystal system, the squeezed-coherent state expansion method is used to account for the electron-phonon quantum correlation and renormalization shift correction, and the analysis and study of the interaction between the electron-dipole interaction and the polaron-soliton system The properties of the ground state and the quantum fluctuations are studied. The closed form nonlinear equations for one-dimensional polaron-soliton systems are deduced. The analytical solutions of the nonlinear equations and the related ground state properties are given by using the nonlinear term expansion method. The soliton solution of the nonlinear equation is obtained only when the electron-diphone coupling strength is g1 <0. At this time, the quantum fluctuation effect of phonons becomes more negative as the compression increases. The ground state energy of the polaron-soliton system becomes more negative. On the other hand, the electron density fluctuation <Δ2n> and the phonon coordinate - the uncertainty of the momentum <Δ2p> <Δ2q> are larger than those of the silent phonon compression, and the polaron binding energy becomes In particular, when g1 <0, the quantum fluctuations of the phonon effect <Δ2n> and <Δ2p> <Δ2q> are significantly higher than those of the mono phonon.