Valley-polarized pumping current in zigzag graphene nanoribbons with different spatial symmetries*

Project supported by the National Natural Science Foundation of China (Grant Nos. 11704190, 11874221, and 11504240) and the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20171030).
Yu Zhizhou1, †, Xu Fuming2
       

(color online) Valley-polarized pumping current of symmetric ZGNRs as a function of the phase difference ϕ1k with a static potential V0 = 0.2 V and a pumping potential Vp = 50 mV at Ef = −0.076 eV for different spatial symmetries. A factor of 100 and 10 is multiplied to and for illustration, respectively. The dashed blue line denotes the valley polarization of pumping current as a function of the phase difference. Inset: Valley-polarized pumping current as a function of the phase difference ϕ12 with a static potential V0 = 0.2 V and a pumping potential Vp = 10 mV at Ef = −0.076 eV.