A triple lattice site quantum wire (QW) system is chosen to investigate nonequilibrium spin transport properties theoretically. We calculate the initial charge of the QW from the exactly derived ground state. Based on the Keldysh formalism, we describe theoretical methods and derive analytical formulas for nonequilibrium spin transport of the QW systems within Hartree-Fock approximation when Coulomb interactions are present. We report the numerical results of the nonequilibrium differential spin conductance, spin transport current, and electronic charge distribution of the triple site QW system. When only including Coulomb repulsions between the spin-up and spin-down electrons, the series of peaks and valleys in the conductance characteristics appears due to the spin resonant tunneling and spin blockade. With the increase of Coulomb interaction energy U, the conductance peaks start to split into two corresponding to the spin-up and spin-down conductance. Near the resonant points, the spin current polarization and the in-site spin charge polarizations take place. When additionally including spin-spin interactions, the differences between the spin-up and spin-down conductance characteristics are reduced, implying that the spin split is relaxed by spin-spin interactions. The spin splits, the spin current, and spin charge polarizations are relaxed at high temperatures due to the thermal fluctuations.

从理论上研究了三晶格量子线（QW）系统来研究非平衡自旋输运性质。我们从精确导出的基态计算QW的初始电荷。基于Keldysh形式主义，我们描述了理论方法并推导了当存在库仑相互作用时，在Hartree-Fock近似内QW系统的非平衡自旋输运的解析公式。我们报告了非平衡差分自旋电导，自旋输运电流和三站点QW系统的电子电荷分布的数值结果。当仅包括自旋向上和自旋向下的电子之间的库仑斥力时，由于自旋共振隧穿和自旋阻断，电导特性中出现一系列峰和谷。U，电导峰开始分成与自旋上升和自旋下降电导相对应的两个。在谐振点附近，发生自旋电流极化和现场自旋电荷极化。当另外包括自旋-自旋相互作用时，自旋向上和自旋向下电导特性之间的差异减小，这意味着自旋-自旋相互作用使自旋分裂松弛。由于热波动，自旋分裂，自旋电流和自旋电荷极化在高温下松弛。