A fully funded PhD opportunity to participate in the world-leading research undertaken by the EPSRC Doctoral Landscape Award at the University of Sheffield.
The unique properties of particles of light (photons) can enable a host of new technologies, such as quantum computing and networking. However, the realization of these technologies requires scalable and efficient sources of quantum light. Quantum dots (QDs) are an excellent candidate with which to implement these sources - they are nanoscale artificial atoms within bulk semiconductors, exhibiting strong light-matter interactions and confining single electron spins. By manipulating this electron spin with laser pulses, a string of entangled photons can be generated. These “photonic resource states” have extensive applications in optical quantum technologies such as photonic computing and long-range secure networking.
However, many challenges still remain. Current QD spin-photon interfaces suffer from strong environmental interactions between the electron spin and the host environment, causing a rapid loss of spin coherence that greatly limits the size and fidelity of the photonic states that can be generated. Furthermore, conventional QD materials lead to the emission of photons at wavelengths that do not align well with key technologies such as low-loss optical fiber networks, limiting their potential applications.
To overcome these limitations, this project will focus on developing spin-photon interfaces using emerging QD materials with advantageous properties. Several different materials systems will be investigated, focusing on tailoring the semiconductor structures to reduce nuclear spin noise and achieve photon emission at technologically important wavelengths such as telecommunications bands. In this way, this project will support the development of a new generation of solid-state quantum light sources, achieving the significant advances in photonic resource state size and fidelity that are required to scale-up optical quantum technologies for real-world applications.
The project will involve close collaboration with other Sheffield researchers on the growth and nanofabrication of the QD samples. Extensive experimental work will be carried out in our state-of-the-art laboratories, using advanced techniques such as cryogenic magneto-optical spectroscopy, ultrafast laser pulse shaping and photon correlation measurements to characterise both the QD samples and the resulting entangled photon states.
Thanks to the collaborative nature of this project, the successful applicant will also have the opportunity to undertake placements and collaborative research with Aegiq, a Sheffield-based quantum photonics company. This will provide a unique opportunity to explore the pathway from fundamental quantum optics research through to real-world optical quantum technologies, with Aegiq’s first Artemis photonic quantum computing testbed recently installed at the National Quantum Computing Center.
The University of Sheffield is one of the leading Russell Group universities in the UK. We carry out cutting-edge research with strong links to industry. When you enrol to do a PhD with us, you will be working with world-leading academics and have access to top of the range facilities. As a PhD student you will have the opportunity to gain skills not only to conduct research, but also to take your career to the next level, whether you want to stay in academia, go into industry or the public sector, or set up your own company. You will have access to a range of training and support services to help you excel in your studies and beyond.
How to apply
Interested candidates are strongly encouraged to contact the project supervisors to discuss your interest in and suitability for the project prior to submitting your application.
Please refer to the EPSRC DLA webpage for detailed information about the EPSRC DLA and how to apply.
