2023-24-project-catalogue

###Engineering Correlation Effects in Quantum Structures

Project ID: 2228bd1175 (You will need this ID for your application)

Research Theme: Quantum Technologies

UCL Lead department: Electronic and Electrical Engineering (EEE)

Department Website

Lead Supervisor: Sanjeev Kumar

Project Summary:

This PhD project will involve investigating fractional quantisation of conductance in one-dimensional semiconductor nanostructures for discovering new quantum phenomena for quantum technologies. Recently, it was shown that low-dimensional electrons when perturbed could give rise to novel phenomena leading to fractions in quantum conductance (e^2/h). This unexpected observation could be vital for topology and the next generation of quantum computing.

A variety of experimental samples will be utilised such as coupled and uncoupled single and bilayer electron gases formed in semiconductor heterostructures. Firstly, suitable experimental conditions will be optimised for measuring fractional conductance plateaus in shallow confined quasi-one dimensional quantum wires in the single electron gas, then repeated in complex systems comprising bilayer systems. A bilayer system provides an outstanding platform to investigate quantum transport as the separation between electrons can be as close as the Bohr radius; therefore the quasi-particles which give rise to a fractional quantisation in conductance could be investigated in a variety of interacting regimes. The project is experimental in nature in collaboration with theorists and will involve training in the cleanroom for high-quality device fabrication and low-noise measurements at extremely low temperatures and high magnetic fields.

The project is original and inspired by a recent discovery on manipulating wavefunction in low-dimensional semiconductors for new quantum particles. The project will have many applications for the next generation of quantum computing devices and for exploring new fundamental quantum condensed matter physics. The project will bring new insight into understanding how electronic charge could be fractionalised by merely confining electrons in narrow low-dimensional channels under strong electron-electron interactions, thus paving the way for realising new rules for the ballistic fractional quantum resistor. The group has expertise in the field; therefore the chances of finishing the project within the timeframe are very high.