Ca intercalated bilayer graphene as a thinnest limit of superconducting C 6 Ca
Year: 2012
Type: article
Abstract: Success in isolating a 2D graphene sheet from bulky graphite has triggered intensive studies of its physical properties as well as its application in devices. Graphite intercalation compounds (GICs) have provided a platform of exotic quantum phenomena such as superconductivity, but it is unclear whether such intercalation is feasible in the thinnest 2D limit (i.e., bilayer graphene). Here we report a unique experimental realization of 2D GIC, by fabricating calcium-intercalated bilayer graphene C(6)CaC(6) on silicon carbide. We have investigated the structure and electronic states by scanning tunneling microscopy and angle-resolved photoemission spectroscopy. We observed a free-electron-like interlayer band at the Brillouin-zone center, which is thought to be responsible for the superconductivity in 3D GICs, in addition to a large π* Fermi surface at the zone boundary. The present success in fabricating Ca-intercalated bilayer graphene would open a promising route to search for other 2D superconductors as well as to explore its application in devices.
Authors: Kohei Kanetani, Katsuaki Sugawara, Takafumi Sato, Ryota Shimizu, Katsuya Iwaya, Taro Hitosugi, Takashi Takahashi
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Awards: Electronic states of novel functional materials studied by ultrahigh-resolution three-dimensional spin- and angle-resolved photoemission spectroscopy, Novel physical properties of layer-controlled graphene, Bulk electronic states of high-Tc cuprate superconductors studied by high-resolution angle-resolved photoemission spectroscopy, Restructuring materials design principles of d-electron based transparent conducting oxide
OpenAlex ID: W2020795371