Coexistence of Midgap Antiferromagnetic and Mott States in Undoped, Hole- and Electron-Doped Ambipolar Cuprates.

摘要: We report the first observation of coexistence a distinct midgap state and Mott in undoped their evolution electron hole-doped ambipolar Y_{0.38}La_{0.62}(Ba_{0.82}La_{0.18})_{2}Cu_{3}O_{y} films using spectroscopic ellipsometry x-ray absorption spectroscopies at O K Cu L_{3,2} edges. Supported by theoretical calculations, is shown to originate from antiferromagnetic correlation. Surprisingly, while magnetic collapses its correlation strength weakens with dopings, contrast moves toward higher energy increases. Our result provides important clues mechanism electronic strengths superconductivity cuprates.