Experimental aspects of superconductivity in layered structures

The experimental work done on layered systems to date is reviewed. The occurrence of superconductivity in the pure compounds and the effects of non-stoichiometry and impurities are discussed. The superconducting parameters for the pure compounds and the effects of pressure are considered. Metallic compounds intercalated with organic molecules and layered compounds intercalated with metals are discussed. The different approach to the possibility of 'two-dimensional' superconductivity given by measurements on ultra-thin crystals of 2H-NbSe2 is considered. The flux flow and critical currents in 2H-NbSe2 are also discussed. (B.R.H.)