We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an a...We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an arc with central angleφ.We find that the bending strain reduces the conductance but enhances the valley polarization.In the valley-resolved conductance spectra,there exist single-valley plateaus near the Dirac points and distinct Fano-type dips.Accordingly,a plateau of full valley polarization appears,which expands significantly at largeφ.At valleyresolved conductance dips,the valley polarization can be much larger than that in the unstrained case.The bending-induced enhancement of valley polarization can be explained by the features of pseudo-Landau levels in the bent region.Strain-induced valley polarization depends nonmonotonously on the nanoribbon width.These findings could be helpful in designing valleytronic devices with flexibility.展开更多
基金supported by the public welfare project(Normal Education Quality Improvement Plan)by the China Education Development Foundation(Grant No.TZJH202202)the National Natural Science Foundation of China(Grant No.12274370)。
文摘We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an arc with central angleφ.We find that the bending strain reduces the conductance but enhances the valley polarization.In the valley-resolved conductance spectra,there exist single-valley plateaus near the Dirac points and distinct Fano-type dips.Accordingly,a plateau of full valley polarization appears,which expands significantly at largeφ.At valleyresolved conductance dips,the valley polarization can be much larger than that in the unstrained case.The bending-induced enhancement of valley polarization can be explained by the features of pseudo-Landau levels in the bent region.Strain-induced valley polarization depends nonmonotonously on the nanoribbon width.These findings could be helpful in designing valleytronic devices with flexibility.
