Metal-intercalated aromatic hydrocarbons: a new class of carbon-based superconductors

Abstract

New carbon-based superconductors are synthesized by intercalating metal atoms into the solid-phase hydrocarbons picene and coronene. The highest reported superconducting transition temperature, T_c, of a hydrocarbon superconductor is 18 K for K₃picene. The physics and chemistry of the hydrocarbon superconductors are extensively described for A_xpicene (A: alkali and alkali earth-metal atoms) for x = 0–5. The theoretical picture of their electronic structure is also reviewed. Future prospects for hydrocarbon superconductors are discussed from the viewpoint of combining electronics with condensed-matter physics: modification of the physical properties of hydrocarbon solids is explored by building them into a field-effect transistor. The features of other carbon-based superconductors are compared to clarify the nature of hydrocarbon superconductors.