Optical conductivity and superconductivity in highly overdoped La2—xCaₓCuO₄ thin films

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 118; no. 30; pp. 1 - 5
• Main Authors: Kim, Gideok, Rabinovich, Ksenia S., Boris, Alexander V., Yaresko, Alexander N., Suyolcu, Y. Eren, Wu, Yu-Mi, van Aken, Peter A., Christiani, Georg, Logvenov, Gennady, Keimer, Bernhard
• Format: Journal Article
• Language: English
• Published: Washington National Academy of Sciences 27.07.2021
• Subjects: Calcium ions; Conductivity; Cuprates; Epitaxial growth; Mean field theory; Molecular beam epitaxy; Phase diagrams; Physical Sciences; Spectroellipsometry; Superconductivity; Thin films

We have used atomic layer-by-layer oxide molecular beam epitaxy to grow epitaxial thin films of La2—xCaₓCuO₄ with x up to 0.5, greatly exceeding the solubility limit of Ca in bulk systems (x ∼ 0.12). A comparison of the optical conductivity measured by spectroscopic ellipsometry to prior predictions...