Enhanced many-body effects in one-dimensional linear atomic chains

We present the quasiparticle energy and optical absorption spectrum results of 1D linear H, BN, C, and Au chains, which are the lower size limit of a periodic material, by using ab initio many-body approaches. Unprecedentedly large quasiparticle corrections and excitonic effects are revealed in these extreme systems compared with quasi-1D, 2D, and 3D periodic systems. The binding energy of the bound exciton is up to 3.55eV in the semiconducting BN chain and 0.5eV in the metallic C chain, the latter of which is the largest in a metallic system.