EPSRC DTP PhD studentship: The demonstration of room temperature (RT) quantum electrical analogues of optical elements and circuits

University of Exeter - Departments of Physics and Astronomy, and Department of Engineering

The studentship is part of the EPSRC Centre of Doctoral Training in Metamaterials (XM2), www.exeter.ac.uk/metamaterials. Our aim is to undertake world-leading research, while training scientists and engineers with the relevant research skills and knowledge, and professional attributes for industry and academia.

Joint supervisors: Prof Saverio RussoProf Monica Craciun

Quantum information technology holds the promise of a significant impact on society. However, the short quantum coherence time found in standard semiconductor or superconductor-based quantum bits constitutes a serious limitation. Graphene is an ideal candidate for such technologies, as it is a sheet of carbon just one atom thick, with an expected spectacularly long quantum coherence time. This project is directed specifically at tuning the electronic properties of graphene by texturing graphene with arrays of holes, known as antidote lattice, so as to allow the full potential of this material to be exploited in conceptually new quantum technologies. Antidot lattices are uniquely suited to study the cross over from classical to quantum transport in macroscopic devices. Graphene antidot lattices have been shown to solve the problem of the missing band gap in transistor applications and were even predicted to serve as the technological basis for spin qubits. In these structures, magnetotransport is dominated by commensurability features stemming from ballistic orbits around one or several antidots. So far, studies of electrical transport in antidot matrices have always been limited to cryogenic temperatures due to the low charge carrier mobility in nowadays materials. However, this scenario will be revolutionized soon by a recent discovery by the team of Prof Russo and Craciun of a novel encapsulation method which preserves the wave-nature of electrons in graphene at room temperature for long times and long propagation distance. The aim of this PhD project will be to pioneer the study of a room temperature cross over from classical to quantum regime as a function of the size of the antidot array using the pioneering encapsulations methods of graphene needed to attain room temperature quantum ballistic regime. The small feature size of the antidots will allow us to approach the region where the classical picture of cyclotron orbits due to bending of trajectories of electrons by an external magnetic field no longer applies. This classical to quantum crossover is governed by the ratio between the Fermi wavelength λF of the carriers and the dimensions of the nanopattern. Owing to the high quality of the materials we can fabricate at Exeter, we are in a unique position to pioneer the observation of this cross over at room temperature and in macroscopic scale samples.

Funding Details
4-year studentship: for UK/EU students, the studentship includes tuition fees and an annual stipend equivalent to current Research Council rates; for international students (non-EU) a very small number of fees only studentships may be available

Share this PhD
     
  Share by Email   Print this job   More sharing options
We value your feedback on the quality of our adverts. If you have a comment to make about the overall quality of this advert, or its categorisation then please send us your feedback
Advert information

Type / Role:

PhD

Location(s):

South West England