Density functional theory (DFT) has been the most popular method for understanding the electronic structure of materials from first principles for over 30 years, thanks to its balance of computational efficiency, accuracy, and simplicity. Well-developed derivatives of DFT, such as time-dependent DFT (TDDFT), allow for the calculation of response properties, such as the excitation of electrons by the absorption of light.

However, standard (TD)DFT has several well-known systematic issues that limit its utility. The cost of standard DFT scales cubically with the number of electrons, restricting calculations to relatively small systems; linear-scaling DFT has been developed as a way to reduce this scaling and model larger, nanoscale, systems. DFT also often underestimates band gaps, is inaccurate in its treatment of excitons, and is ineffective in systems with strong electron correlation. More advanced techniques are able to address these issues, such as the GW approximation, the Bethe-Salpeter equation (BSE), and wavefunction-based methods, but these often come at a much higher computational cost. This means that, currently, it is very difficult to apply these high-level methods to the complex large-scale materials relevant in many applications, including quantum technology, photovoltaics, and biochemistry.

This project is therefore focused on developing new methods to bring these higher-level techniques to bear on complex systems, by combining them with linear-scaling DFT. The main approach used for this will be quantum embedding, where only a small portion of the system is treated at the high level of theory, with the rest treated at a lower level, maintaining self-consistency throughout. The initial focus would be on embedding GW and BSE methods within linear-scaling DFT, significantly increasing the accuracy of excited state calculations available for complex systems. In the longer term, the project would encompass even higher-level methods, such as wavefunction-based methods. These cutting-edge techniques would be implemented primarily in the ONETEP code, which is developed in the group. To test these newly developed techniques, the project would also involve simulating systems with practical applications, such as defects for quantum technology, or organic photovoltaics.

This project will suit a student with an interest in computational modelling and code development, and a background in physics, chemistry, materials science, or related disciplines. Experience in coding, particularly in Python and FORTRAN, would be beneficial, but not necessary.

Eligibility

Applicants should have, or expect to achieve, at least a 2.1 honours degree or a master’s (or international equivalent) in a relevant science or engineering related discipline.

Funding

At Manchester we offer a range of scholarships, studentships and awards at university, faculty and department level, to support both UK and overseas postgraduate researchers applying for competition and self-funded projects.

For more information, visit our funding page or search our funding database for specific scholarships, studentships and awards you may be eligible for.

Please discuss funding option with the supervisor.

Before you apply

We strongly recommend that you contact the supervisor for this project before you apply. Please include details of your current level of study, academic background and any relevant experience and include a paragraph about your motivation to study this PhD project.

How to apply

Apply online through our website: https://uom.link/pgr-apply-2425

When applying, you’ll need to specify the full name of this project, the name of your supervisor, if you already having funding or if you wish to be considered for available funding through the university, details of your previous study, and names and contact details of two referees.

Your application will not be processed without all of the required documents submitted at the time of application, and we cannot accept responsibility for late or missed deadlines. Incomplete applications will not be considered.

After you have applied you will be asked to upload the following supporting documents:

• Final Transcript and certificates of all awarded university level qualifications
• Interim Transcript of any university level qualifications in progress
• CV
• Supporting statement: A one or two page statement outlining your motivation to pursue postgraduate research and why you want to undertake postgraduate research at Manchester, any relevant research or work experience, the key findings of your previous research experience, and techniques and skills you’ve developed. (This is mandatory for all applicants and the application will be put on hold without it).
• Contact details for two referees (please make sure that the contact email you provide is an official university/work email address as we may need to verify the reference)
• English Language certificate (if applicable)

If you have any questions about making an application, please contact our admissions team by emailing [email protected] .

Equality, diversity and inclusion is fundamental to the success of The University of Manchester, and is at the heart of all of our activities. We know that diversity strengthens our research community, leading to enhanced research creativity, productivity and quality, and societal and economic impact.

We actively encourage applicants from diverse career paths and backgrounds and from all sections of the community, regardless of age, disability, ethnicity, gender, gender expression, sexual orientation and transgender status.

We also support applications from those returning from a career break or other roles. We consider offering flexible study arrangements (including part-time: 50%, 60% or 80%, depending on the project/funder).