title: Controlled Modification of Superconductivity in Epitaxial Atomic Layer-Organic Molecule Heterostructures.
abstract: Self-assembled organic molecules can potentially be an excellent source of charge and spin for two-dimensional (2D) atomic-layer superconductors. Here we investigate 2D heterostructures based on In atomic layers epitaxially grown on Si and highly ordered metal-phthalocyanine (MPc, M = Mn, Cu) through a variety of techniques: scanning tunneling microscopy, electron transport measurements, angle-resolved photoemission spectroscopy, X-ray magnetic circular dichroism, and ab initio calculations. We demonstrate that the superconducting transition temperature (Tc) of the heterostructures can be modified in a controllable manner. Particularly, the substitution of the coordinated metal atoms from Mn to Cu is found to reverse the Tcshift from negative to positive directions. This distinctive behavior is attributed to a competition of charge and spin effects, the latter of which is governed by the directionality of the relevant d-orbitals. The present study shows the effectiveness of molecule-induced surface doping and the significance of microscopic understanding of the molecular states in these 2D heterostructures.
authors.affiliation: International Center for Young Scientists (ICYS), National Institute for Materials Science , 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Shunsuke
authors.identifier: 0000-0003-3380-5473
authors.initials: S
authors.lastname: Yoshizawa
authors.affiliation: Department of Materials Engineering, The University of Tokyo , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Minamitani
authors.affiliation: International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science , 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Saranyan
authors.initials: S
authors.lastname: Vijayaraghavan
authors.affiliation: International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science , 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Puneet
authors.initials: P
authors.lastname: Mishra
authors.affiliation: Institute for Molecular Science , Myoudaiji Campus, 38 Nishigo-Naka, Myodaiji, Okazaki, Aichi 444-8585, Japan.
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Takagi
authors.affiliation: Institute for Molecular Science , Myoudaiji Campus, 38 Nishigo-Naka, Myodaiji, Okazaki, Aichi 444-8585, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yokoyama
authors.affiliation: Department of Nanomaterials Science, Graduate School of Advanced Integration Science, Chiba University , 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Oba
authors.affiliation: Department of Nanomaterials Science, Graduate School of Advanced Integration Science, Chiba University , 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nitta
authors.affiliation: Department of Nanomaterials Science, Graduate School of Advanced Integration Science, Chiba University , 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Sakamoto
authors.affiliation: Department of Materials Engineering, The University of Tokyo , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science , 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science , 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Takashi
authors.identifier: 0000-0003-0811-5665
authors.initials: T
authors.lastname: Uchihashi
keywords: Superconductivity; atomic layer; carrier doping; molecular self-assembly; spin; surface