▎ 摘 要
We study the effect of the gauge potential (A) over right arrow (S) induced by a local strain on electronic transport in a strain engineered graphene junction. For the normal/strained/normal/strained/normal graphene junction, by changing the sign of (A) over right arrow (S) the K and K' valleys are interchanged, the conductance can change from finite to zero, so we obtain the valley valve effect. For the ferromagnetic/strained/ferromagnetic graphene junction in the parallel magnetization configuration by adjusting the gauge potential strength A(S) only the incident electrons in the spin-down channel are allowed to transmit, thus we can observe the strain-tunable spin filter effect. The magnetoresistance increases with A(S) and can reach up to 100%. It is expected these features may be helpful in the design of the strain-tunable spintronic devices. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4720386]