Guiding Electrons and Spin through a Graphene Sheet and related systems

We will produce and probe anisotropic behaviour of electrons within the graphene sheet and waveguide their trajectories, exploiting graphene’s very peculiar, Dirac physics. The work will be extended to Topological Insulators, which exhibit similar Dirac physics but where electrons are spin polarized. Waveguiding of electrons and spin will open entirely new applications in fields such as Information Technology and spintronics.

Details of the Project
In graphene systems, unconventional quantum phenomena - such as anisotropic, highly directional quantum tunnelling - occur when electrons encounter potential barriers, due to the very peculiar physics of the Dirac electrons within graphene, whose wavefunction has a spinor (chiral) form. As a result of this, by controlling and modulating the surface potential of the graphene sheet one can guide electrons or collimate them. Here, we will engineer the potential distribution within the graphene sheet through bottom-up, atomically-controlled engineering of the underlying substrate, as well as functionalization of graphene surface with molecular or inorganic systems, in order to control and manipulate the flow of electrons within the graphene sheet. We will then provide direct evidence of waveguiding through combined scanning probe microscopy (e.g. Scanning Tunneling Microscopy and its variants) and electron transport.

This approach will be extended to systems which exhibit similar Dirac physics but where electrons are spin polarized – this occurs on the surface of a Topological Insulator, a class of materials insulating in the bulk and conducting on the surface, but where the surface currents are 100% spin polarized.

A unique, scanning probe-based nanofabrication and imaging “nano-factory” will be used to produce these systems and probe their unique properties. This will combine characterization at the atomic level using Scanning Tunneling Microscopy and non-contact Atomic Force Microscopy (in Ultra-High Vacuum), with in-situ bottom-up nanofabrication of nano-devices and correlated investigations of electron transport properties.

The work will take place in the Centre for Graphene Science/Department of Physics, where the student will be integrated, under the supervision of Dr. Adelina Ilie. The work will involve complementary collaborations with nanoscience and chemistry groups within the University, Japan and Europe.

Contact Dr Adelina ILIE ([Email Address Removed]) for further information on the project. Website: http://people.bath.ac.uk/ai213/ .

This is a re-advertisement and previous applicants should contact the supervisor if they still wish to be considered.