Origin of shadow bands in high-Tc cuprate superconductors studied by high-resolution angle-resolved photoemission spectroscopy

We report high-resolution angle-resolved photoemission spectroscopy on single-layered cuprate superconductor (Bi,Pb)2(Sr,La)2CuO6+δ as a function of temperature and doping level, to elucidate the origin of shadow band (SB). We found that the intensity of SB is invariable with respect to temperature, doping, and substitution constituents of block layers, indicating that antiferromagnetic correlation is not responsible for the emergence of SB. Observation of similar SB in Bi2Sr2CaCu2O8+δ and La1.85Sr0.15CuO4, but not in YBa2Cu3O7−δ further supports the structural origin of SB.