▎ 摘　　要

Tunable terahertz (THz) absorber is a hot research topic in recent years. However, absorption peak number control is rarely studied. A multi-band THz absorber based on a horizontal array of vertically offset graphene nanoribbon pairs is proposed and numerically investigated. By asymmetrically widening the lower layer gra-phene nanoribbons, two new absorption peaks are added due to the effective excitations of even-mode lateral Fabry-Perot resonances. By different Fermi energy applying strategies, doubling and tripling of the absorption peak number can be realized. Besides, the relatively simple device structure reduces the difficulty of subsequent fabrications. The proposed peak number controllable multi-band THz absorber shows promise in the areas of sensing, non-destructive testing, explosive detection and etc.