Surface physics; Thin films; Synthesis of materials; Laser ablation.
My group has pioneered the use of laser ablation methods for the synthesis of advanced materials, and in 1993 published a report of the synthesis of microcrystalline diamond using laser ablation of a solid carbon source, without auxiliary energy sources. More recently, structurally related cubic boron nitride films have been deposited by ion-assisted pulsed laser ablation. These methods, as well as bias-assisted hot filament chemical vapour deposition were utilised for the synthesis of carbon nitride (C3N4), a material with a bulk modulus estimated to exceed that of diamond itself. The laser ablation method is also particularly suited to the fabrication of ferroelectric films, specifically multilayered ferroelectric thin films that clearly show the formation of superlattices and allow tailoring of dielectric properties. This multilayer technique has been extended to produce superhard superlattices that possess hardness values enhanced by two to three with respect to individual layer materials at critical periodicities (typically 2 nm).