University of Exeter funding: Chalcogenide-based memory and logic

CDT in Metamaterials: Chalcogenide-based memory and logic for flexible electronics applications Ref: 3447

About the award

Statement of Research

Joint supervisors: Prof C D Wright, Prof M F Craciun

External partners: PragmatIC Ltd (Dr C Ramsdale); University of Southampton (Prof D Hewak)

Here we will explore the use of ultra-thin and 2D chalcogenide semiconductor materials for the provision of non-volatile, re-writable phase-change memories and logic suited to flexible electronics applications. The project is sponsored by PragmatIC (, who are developing ultra-low cost flexible integrated circuits (FlexICs) thinner than a human hair that can easily be embedded into everyday objects enabling smart packaging, smart labels and smart objects that interact with consumers and their environments. In preliminary work [1-3] we have already shown that both 2D and low-dimensional chalcogenide alloys are suited to use in flexible systems (in the former the phase-transition is between semimetal and semiconducting phases, in the latter between amorphous and crystalline phases). However, very significant challenges remain in terms of materials development and device design so as to meet the requirements (e.g. high numbers of switching cycles, low-energy switching, fast switching speed, true non-volatility, longevity) for real-world applications. In this project, therefore, we will address such challenges by developing (i) novel phase-change device configurations for integration into flexible electronics formats and (ii) new chalcogenide phase-change compositions, new 2D heterostructures and new low-temperature (physical vapour deposition) approaches to the large-area fabrication of 2D materials. The research for this project will be carried out primarily at Exeter, but with placement opportunities with PragmatIC at both their Cambridge (research) and NETPark Sedgefield (manufacturing) sites.

[1] Hosseini P, Wright CD, Bhaskaran H An optoelectronic framework enabled by low-dimensional phase-change films, Nature, 511, 206-211, DOI:10.1038/nature13487 (2014)

[2] Alkhalil F, Ramsdale C, Au Y Y, Zeimpekis I, Hewak D and Wright CD, Phase-Change Memory for Flexible Electronics,, InnoLAE 2018 Conference (2018)

[3] Nagareddy VK, Octon T J, Townsend NJ, Russo S, Craciun MF and Wright CD, Humidity‐Controlled Ultralow Power Layer‐by‐Layer Thinning, Nanopatterning and Bandgap Engineering of MoTe2, Advanced Functional Materials, (2018)

The studentship is part of the UK’s Centre of Doctoral Training in Metamaterials (XM2) based in the Departments of Physics and Engineering on the Streatham Campus in Exeter.  Our aim is to undertake world-leading research, while training scientists and engineers with the relevant research skills and knowledge, and professional attributes for industry and academia.

This 3.5 year PhD studentship will cover UK tuition fees, an annual tax-free stipend at approx. £15,000 per year (UK/EU students only), plus a Research and Training Support Grant (RTSG) of £1,500.

The studentship will be aligned to the CDT in Metamaterials to enable access to comprehensive technical and transferable skills training.

Exeter has a well-established and strong track record of relevant research, and prospective students can consider projects from a wide variety of fields:

  • Acoustic and Fluid-dynamical Metamaterials
  • Biological and Bio-inspired Metamaterials
  • Graphene and other 2D Materials, and related Devices
  • Magnonics, Spintronics and Magnetic Metamaterials
  • Microwave Metamaterials
  • Nanomaterials and Nanocomposites
  • Optical, Infra-red and THz Photonics and Plasmonics
  • Quantum Metamaterials
  • Wave Theory and Spatial Transformations

Please visit to learn more about our centre and see the full list of projects that we have on offer this year.

The studentship is subject to funding availability.

About XM2

Metamaterials are fabricated microstructures having properties beyond those found in nature. They are an important new class of electromagnetic and acoustic materials with applications in many technology areas: energy storage and improved efficiency, imaging, communications, sensing and the much-hyped ‘cloaking’. Since 2014, the Centre for Doctoral Training in Metamaterials (XM2) recruited more than 80 PhD students. Learn more about our science and training approach:

The first year of the studentship includes an assessed, stand alone project, and a substantial programme of training. Students will choose from a wide range of taught modules, and participate in academic and personal development skills-based workshops, together with creativity events and conference-style meetings. The cohort will also be expected to disseminate their results to the international community via high-impact publications and international conferences. They will spend time working with our academic and industrial partners.  Full details of the programme are available here.

The University of Exeter combines world class research with excellent student satisfaction. It is a member of the Russell Group of leading research-intensive universities. Formed in 1955, the University has over 20,000 students from more than 130 different countries. Its success is built on a strong partnership with its students and a clear focus on high performance. Recent breakthroughs to come out of Exeter's research include the identification and treatment of new forms of diabetes and the creation of the world's most transparent, lightweight and flexible conductor of electricity. Exeter is ranked amongst the UK’s top 10 universities in the Higher Education league tables produced by the Times and the Sunday Times. It is also ranked amongst the world’s top 200 universities in the QS and Times Higher Education rankings.

How to apply

Application criteria

During the application process you will need to upload the documents listed below. Please prepare these before starting the application process.

  • Degree transcript(s) giving information about the qualification awarded, the modules taken during the study period, and the marks for each module taken.
  • An academic CV;
  • A cover letter outlining your research interests in general, the title of the project you are applying for;
  • A Personal Statement consisting of two parts*:
    • Describe a) why you would like to study for a PhD, b) why you would like to focus on this particular topic, c) any relevant expertise and d) your future career ambitions;
    • Describe the qualities that you believe will make you a great researcher (in particular as part of a team).

You will be asked to provide the contact details of two academic referees.

* We foster creativity and utilisation of individual strengths. Applicants are encouraged to provide evidence to support their statements. This might include conventional written documents (e.g. examples of work), but we also encourage alternatives such as audio or video recordings, websites, programming etc. Please ensure to include accessible links to such files in an appropriately named document as part of the upload process.

Application procedure


Applications will normally be reviewed within two weeks of receipt.
Candidates will be short-listed against a set of agreed criteria to ensure quality while maintaining diversity. Failure to include all the elements listed above may result in rejection.

The essential criteria:

  • Undergraduate degree in a relevant discipline (minimum 2:1);
  • Vision and motivation (for research & professional development);
  • Evidence of the ability to work collaboratively and to engage in a diverse community;
  • Evidence of excellent written and oral skills in English.

The highest quality candidates will also be able to demonstrate one of more of the following:

  • Specialist knowledge about one or more of the 8 research areas listed above;
  • Training in research methodology (e.g. undergraduate research projects);
  • Research outputs (e.g. papers) and/or other indicators of academic excellence (e.g. awards).


Shortlisted candidates will be invited to an entry interview to assess fit to the CDT concept. This will be held prior the academic interview with the supervisors and will normally be undertaken by a panel of 3 people, including a current postgraduate researcher or post-doc in Physics or Engineering.

Please email if you have any queries about this process.


Application deadline:31st December 2019
Number of awards:1
Value:Approx. £70,000 for 42 months (pro-rata for part-time study): covers UK/EU tuition fees, an annual tax-free stipend at £15,000 per year, plus £1,500 RTSG.
Duration of award:per year
Contact: Dr. Isaac Luxmoore (Admissions Tutor)