Bulk crystals of electron-doped cuprates with a $T^{\prime }$-type structure require both Ce substitutions and reduction annealing for the emergence of superconductivity while reduction annealing alone can induce superconductivity in thin films of $T^{\prime }$-type cuprates. In order to reveal the low-energy electronic states which are responsible for the superconductivity, we have conducted angle-resolved photoemission spectroscopy measurements on thin films of the superconducting Ce-free $T^{\prime }$-type cuprate ${\mathrm{Pr}}_2{\mathrm{CuO}}_4$. The results indicate that the overall band structure and the Fermi surface area of the superconducting ${\mathrm{Pr}}_2{\mathrm{CuO}}_4$ are similar to those of superconducting Ce-doped bulk single crystals, highlighting the importance of the actual electron concentration rather than the Ce concentration when discussing the physical properties of $T^{\prime }$-type cuprates.

• Received 11 January 2018
• Revised 28 May 2018

DOI:https://doi.org/10.1103/PhysRevB.98.020505