▎ 摘　　要

In the search for high-sensitivity, low-noise, and high-bandwidth photodetectors, materials are a key ingredient. One- and two-dimensional materials are of particular interest in this area due to their extraordinary properties such as ballistic transport. Here, we demonstrate nanoscale photoconductive photodetectors using aligned atomically precise seven-atom wide armchair-edge graphene nanoribbons. The detector responsivity is 0.035 mAW(-1) at a bias voltage of 2 V. The dark current is below 30 pA for a bias voltage of 1.5 V, which is orders of magnitude lower than that of typical graphene photodetectors. The possibility to align the nanoribbons and to tune their optical and electronic properties by choice of ribbon width and edge structure enables nanoscale polarization-resolving photodetectors optimized for specific spectral ranges. Graphene nanoribbons with identical electronic and optical properties can be prepared on a large scale using bottom-up synthesis, making them a highly interesting material for electronics and optoelectronics.