▎ 摘 要
We measured the polarization dependence of the photocurrent in symmetric Pd-graphene-Pd photodevices. The photocurrent is maximum when the polarization angle of the incident light is parallel to the edge of an electrode. On the other hand, when the polarization direction is parallel to the graphene channel, the photocurrent is minimum. This polarization dependence of the photocurrent is similar to what has been observed in an asymmetric Pd-graphene-Ti device and results from an anisotropic electron-photon interaction in graphene, which generates photocarriers with momenta predominantly in the direction perpendicular to the polarization direction.