Tony Childs
Nanoscale Device Research
Research Topics
Current and recent activities
- Charge transport in MoS2 structures
Currently we are undertaking ab initio calculations on Molybdenum disulphide.
Future work will focus on modelling charge transport in MoS2 devices
- Measurement of the electronic properties of metallic single-walled
carbon nanotubes
(in conjuction with Prof Adrian Porch at Cardiff University)
Using a 3 GHz microwave host cavity we have studied the remarkable electronic properties of metallic, single-walled carbon nanotubes.
Powder samples are shown to screen effectively the microwave magnetic field, implying an extremely low value of sheet resistance
(less than 10 micro Ohm) within the graphene sheets making up the curved nanotube walls. Associated microwave
losses are large due to the large surface area,
but also point to a similar, very small value of sheet resistance due to the inherent ballistic electron transport
[1].
- Modelling of graphene based devices
The discovery of stable graphene at the University of Manchester, UK, has resulted in the rapid growth of research based on this system.
From the devices point of view graphene is of considerable interest due to its compatiblity with planar systems and the high mobility of electrons.
We are currently undertaking simulations of charge transport within graphene based MOS transistors using the Non-Equilibrium Green's Function technique [2,3].
- X-ray propagation in carbon nanotubes
The aim of this EPSRC funded project was to demonstrate experimentally x-ray propagation in carbon nanotubes. Birmingham and Newcastle Universities
have shown through simulation that carbon nanotubes will act as soft x-ray waveguides and support modes of propagation when coated with various materials.
Carbon nanotubes were grown at Cambridge University on top of a silicon membrane.
Following coating of the nanotubes with metal x-ray measurements were made at the Daresbury laboratory to assess the feasibility of propagation.
Theoretical studies of x-ray propagation in Multiwalled CNTs were reported in the Journal of Applied Physics [4].