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 known doping evolution of the structural isomer La2-xSrxCuO4 with sixfold octahedral coordination. In addition, quantitatively characterized Fermi surface suggests that the empirical Tc rule for octahedral oxygen-coordination systems does not apply to T∗-SmLa1-xSrxCuO4. The present results highlight unique properties of the T∗-type cuprates possibly rooted in its oxygen coordination, and necessitate thorough investigation with careful evaluation of disorder effects.
Subject classification (UKÄ)
- Inorganic Chemistry