Development of superconducting quantum-limited travelling-wave amplifiers

Over the past 20 years, a series of technical advances in the development of thin-film superconducting materials have provided a foundation for a new class of technologies that can operate with sensitivity at, or even below, the limit imposed by quantum mechanics.  

 We are seeking a Ph.D. student to lead the development and low temperature characterisation of disordered superconducting materials and their application to quantum-limited amplification of microwave signals. This studentship provides a cross-disciplinary opportunity spanning the Astronomy Instrumentation Group (AIG) and the Condensed Matter Physics (CMP) group, whilst also leveraging the close connection to the Institute for Compound Semiconductors (ICS), to develop a core outstanding capability that promises far reaching impact across a wide range of applications including advances in space science, particle physics, quantum computing, and quantum metrology. 

The properties of highly disordered superconducting nitride thin-films (TiN, NbN, NbTiN), while not fully understood, have been shown to be well-suited to building quantum-limited travelling wave amplifiers owing to their anomalous microwave electrodynamics. While there have been recent

demonstrations of this technique, there remains a gulf between the predicted and realised performance that is poorly understood.  

 Central and unique to this studentship is the use of a newly constructed 200-mm wafer compatible deposition capability developed by the AIG. The technique of High-Power Impulse Magnetron Sputtering (HIPIMS) is a relatively new advance in sputtering technology, providing the fine control and diagnostics needed to optimally tune the reactive sputtering process to ensure reliable and repeatable film properties. Furthermore, the studentship will benefit from access to two ultra-low temperature (10-mK) dilution refrigerators that are equipped with the required DC, microwave, and control electronics needed to fully characterise device performance. 

The successful candidate will be encouraged and supported to take advantage of the numerous training resources available from the Doctoral Academy (DA) and annual early-career summer schools that are available through STFC and ESPSRC. These resources are specifically designed for ECRs and cover a wide range of subjects, from performing effective literature reviews and developing scientific writing skills, to more broader strategies for career progression, professional development, and positive mental health. To ensure adherence to the UKRI AREA framework, the dissemination and societal impact of the outputs resulting from this studentship will be continually reviewed within the supervisory team in consultation with the Director of Innovation and Engagement (Dr Leandro Beltrachini), and, when necessary UKRI. 

How to apply:

Applicants should apply to the Doctor of Philosophy in Physics and Astronomy with a start date of 1st October 2025. 

Applicants should submit an application for postgraduate study via the Cardiff University webpages (https://www.cardiff.ac.uk/study/postgraduate/research/programmes/programme/physics-and-astronomy) including: 

• your academic CV (Guidance on CVs for a PhD position can be found on the FindAPhD website)

• your degree certificates and transcripts to date including certified translations if these are not in English 

• a personal statement/covering letter 

Ensure your personal statement (as part of the university application form, or as a separate attachment, if you prefer) provides a clear explanation of your research interest, preparation undertaken, and an understanding of the project. 

Your personal statement should be no more than 500 words, and address the following questions:

1. What are your scientific research interests and ambition?

2. How has your academic and/or professional journey prepared you for PhD study? (for instance, give examples of work you particularly enjoyed, of challenges you overcame, of connecting with others about your work or ideas, of showing inventiveness, of developing new skills and knowledge)

3. Why do you think this project is important?”

• two references (applicants are recommended to have a third academic referee, if the two academic referees are within the same department/school). Your references can be emailed by the referee to physics-admissions@cardiff.ac.uk  

Please note: We are do not contact referees directly for references for each applicant due to the volume of applications we receive.     

Candidates should hold or expect to gain a first-class degree or a good 2.1 (or their equivalent) in Engineering, Physics or a related subject. Desirable skills are knowledge of Quantum Physics, Optics, Semiconductors, Technology, Physics, Engineering.

Applicants whose first language is not English are normally expected to meet the minimum University requirements (e.g. IELTS 6.5 Overall with 5.5 minimum in sub-scores) (https://www.cardiff.ac.uk/study/international/english-language-requirements) 

In the “Research Proposal” section of your application, please specify the project title and supervisors of this project and copy the project description in the text box provided.

In the funding section, please select that you will not be self-funding and write that the source of funding will be EPSRC. 

Once the deadline for applications has passed, we will review your application and advise you within a few weeks if you have been shortlisted for an interview. 

 

Eligibility :

This studentships are available to home and international students. International students will not be charged the fee difference between the UK and international rate. Applicants should satisfy the UKRI eligibility requirements.

For more information, or if there are any questions re application process, please contact Physics and Astronomy PGR Student Support team at Physics-PG@cardiff.ac.uk