Electronic structure of La₂CuO₄ in the T and T' crystal structures using dynamical mean field theory

Abstract

Using Nth order muffin-tin-orbital-based downfolding technique in combination with dynamical mean field theory, we investigate the correlated electronic structure of La₂CuO₄ in the so-called "T" and "T'" crystal structure which serve as the parent compounds for the hole-doped and electron-doped high T_c compounds. La₂CuO₄, which naturally forms in T structure, has been reported to made to form in T' structure by means of special thin-film synthesis technique of replacing La by isovalent RE (RE=Y,Lu,Sm,Gd...) ions [ A. Tsukada et al. Solid State Commun. 133 427 (2005)]. The experimental studies on T'-structured La₂CuO₄ reveal contrasting properties to that in T structure, which we examine by means of electronic structure calculations. Our dynamical mean field calculations show introduction of correlation effect to the one-electron band structure of T'- and T-structured La₂CuO₄, providing metallic solution in one case (T') and insulating solution to another (T).