Influence of oxygen coordination number on the electronic structure of single-layer La-based cuprates
We present an angle-resolved photoemission spectroscopy study of the single-layer T∗-type structured cuprate SmLa1-xSrxCuO4 with unique fivefold pyramidal oxygen coordination. Upon varying oxygen content, T∗-SmLa1-xSrxCuO4 evolved from a Mott-insulating to a metallic state where the Luttinger sum rule breaks down under the assumption of a large holelike Fermi surface. This is in contrast with the