PhD studentship in Quantum Technology for Fundamental Physics

The research project is part of the UK ‘Network of clocks for measuring the stability of fundamental constants’ consortium. The consortium aims to build a network of dissimilar clocks to search for spatio-temporal changes in fundamental constants. Our partners in the network are the National Physical Laboratory, Imperial College London, the University of Birmingham and the University of Sussex.

The goal of the project at Sussex is to measure the frequency of a vibrational transition in molecular nitrogen ions with unparalleled precision and compare it with an electronic transition in calcium ions. The nitrogen ion's vibrational transition and the calcium ion's electronic transition exhibit different sensitivities to the proton-to-electron mass ratio, and therefore any relative changes in the frequencies of these transitions can be used to establish the degree to which the proton-to-electron mass ratio is constant.

In order to measure the vibrational frequency, a single molecular nitrogen ion will be trapped alongside a single calcium ion. The calcium ion will be used to read out the state of the molecule using a quantum logic spectroscopy scheme. A second ion trap system, which will hold a single calcium ion, will be used as a reference for the frequency comparison.  

The project will employ existing systems in the ITCM Group at Sussex and expand it in order to facilitate the frequency comparison. With the two ion traps and the molecular beam line in place, the focus of the project will be to expand the laser system for the vibrational frequency measurement, implement the quantum logic spectroscopy scheme and measure the frequency ratio of the transitions within nitrogen and calcium. 

The ITCM Group, which operates several ion-trap systems for research in quantum information and precision spectroscopy. The group currently consists of two research fellows, six PhD students, two MSc and three undergraduate project students lead by Prof Keller.

 Skills and training:

An important part of this PhD project is the skills development and training. Local training through lecture courses, transferable skills training modules and practical training in the laboratory will be complemented by SEPnet wide training events. These include workshops and training schools.