▎ 摘　　要

We present the first transport property investigation of a-few-nanometer-long armchair graphene nanoribbon (AGNR) p-n junctions by using first-principles method. Intriguingly, family dependent rectification is observed. To be specific, traditional rectification effect in the forward direction is observed in the AGNR p-n junctions with 3n and 3n + 2 widths, whereas reverse rectification effect is observed in the AGNR p-n junctions with 3n + 1 width. The analysis of the spatial distribution of molecular projected self-consistent Hamiltonian eigenstates and the projected density of states give an insight into the observed results.