Jie Deng, Ruowen Wang, Yonghao Bu, Jie Pan, Wei Zhang, Jing Zhou, Lin Wang, Mengdie Shi, Xu Dai, Ye Tao, Jiajun Ma, Tianyuan Cui, Huiming Luo, Junwei Huang, Yujie Zhang, Xiaoshuang Chen
In conventional materials, symmetry breaking induced by spatial inhomogeneities typically confines self-powered photocurrents to edges, corners, or interfaces. In this work, we observe long-range photocurrents with multidomain patterns extending from the contacts into the interior of homogeneous Weyl semimetals (WTe 2 and TaIrTe 4 ) at room temperature. It is revealed that the long-range photocurrent is approximately proportional to the anisotropic divergence of the weighting field (( σS ∇)· E ). By increasing the conductivity anisotropy or enlarging the angle between the material’s a- axis and the channel direction, the gradient of ( σS ∇)· E along the a -axis is reduced, and the decay length of the long-range photocurrent ( L d ) is substantially increased. As a result, a large L d of up to 20.5 μm is achieved in a TaIrTe 4 device with the a -axis oriented perpendicular to the channel direction, far exceeding typical photocurrent decay lengths observed in conventional low-dimensional materials.