We report a theoretical study of single-parameter quantum valley pumping in graphene with a topological line defect via the Keldysh Green’s function method. It is found that the valley pumping currents appear only at large scattering angles, with the negative sign for K valley while positive sign for $K^{\prime }$ valley. The currents following along the direction of the line defect can reach up to 0.1 mA over a large range of Fermi energies and the driving frequencies of an ac-field, which is beneficial for applications. The high currents origin from the asymmetric scattering in the photon-assisted processes and the special characteristics of electronic state distribution in the line defect. In the case of ferromagnetic lead, the two spin currents flow into different leads, respectively.

我们报告了通过Keldysh Green函数法在具有拓扑线缺陷的石墨烯中进行单参数量子谷抽运的理论研究。结果发现，谷底泵浦电流仅在大散射角处出现，K谷底为负号，K谷底为正号。${ķ}^{\prime }$谷。在较大的费米能量和交流电场的驱动频率范围内，沿线缺陷方向跟踪的电流可以达到0.1 mA，这对应用非常有利。高电流源于光子辅助过程中的不对称散射以及线缺陷中电子态分布的特殊特征。对于铁磁导线，两个自旋电流分别流入不同的导线。