Graphene – an atomically thin sheet of carbon atoms – has attracted enormous scientific interest since its discovery in 2003. Awarded with the Nobel Prize only seven years after it was discovered, the material was soon hailed as the next disruptive technology due to superior attributes, being a zero-band gap Dirac semi-metal with large electron mobility.
A related class of atomically thin materials are the layered transition metal dichalcogenides (TMDCs) MX2, composed of hexagonal lattices of transition metal atoms (M) coordinated by chalcogens (X). The more complex composition of TMDCs allows for a number of different crystalline phases with drastically varying electronic properties – ranging from semiconducting, metallic, and superconducting, to more exotic topological phases. The different crystal structures have been shown to be lattice-matched and exhibit atomically sharp boundaries. Considerable interest therefore exists to locally control the phase to define atomic-scale heterostructures to be used in molecular-scale electronic devices.
The project aims at phase-engineering group VI TMDCs (such as MoS2 and WS2). Based on the interest and skill of the student, experimental techniques may include wet-chemical processing of the material, nanofabrication (including electron beam lithography), electron transport, as well as structural and electronic characterization at the atomic-scale, using low-temperature scanning tunnelling microscopy (STM).
Supervisor: Prof. Michael Fuhrer, Dr Bent Weber
See https://www.monash.edu/science/schools/physics/honours/honours-project to apply.