Superconductivity in graphite intercalation compounds

Abstract

The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s [1,2]. This paper recontextualizes the field in light of the discovery of superconductivity in CaC6 and YbC6 in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how this relates to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.Corresponding author. Tel: +44 (0)7792954220 fax: +44 (0)20 7679 7145 e-mail address: mark.ellerby@ucl.ac.uk (Mark Ellerby).

Thermal Conductivity of Graphite-Based Polymer Composites

“…Graphite-intercalated compounds (GICs): GICs result from the insertion of atomic or molecular layers of different chemical species called intercalant between graphene sheets of the host graphite material [5,[12][13][14]. GIC can be categorized into two depending on the character of their bonding, that is, covalent GICs and ionic GICs.…”

Superconducting materials classes: Introduction and overview

“…C5: Superconductivity in graphite intercalation compounds is reviewed in the fifth article, by Smith et al [18] The first material in this class was discovered in 1965. The authors review the early history of these materials, which have T c 's of a few K, and the recent revival of interest with the discovery of superconductivity in C 6 Ca and C 6 Y b, with T c 's up to 12K.…”

Overview on the intercalation of gold into graphite

“…Then many other binary compounds with alkali metals [2,3], alkaline earth elements [4] and some lanthanides [5][6][7] have been synthesized. Among these compounds, some have revealed remarkable physical and chemical properties [8][9][10][11][12][13] so that some of them lead to applications in everyday life [14,15].…”