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  • Global St Andrews PhD scholarship for a joint PhD project with Karlsruhe Institute of Technology – apply by 5th April

    Project details

    This project will bring together materials, optics and laser expertise in St Andrews and Karlsruhe to make a new generation of organic semiconductors lasers. These lasers will use carbon-based semiconductors. The project will involve studying the photophysical and lasing properties of the new materials and then develop lightweight flexible lasers made from them.

    The first laser used a crystal of ruby to amplify light. We aim to make lasers from much more readily available materials. In particular, we will work with organic semiconductors, which are remarkable plastic-like materials that combine the simple fabrication of plastics with the electrical and optical properties of semiconductors. When a voltage is applied to a thin layer of these materials they give out light, and the resulting device is called an organic light-emitting diode (OLED). Very recently we made a major breakthrough showing that an OLED can be integrated with a polymer laser to make an electrically driven laser.

    The most recent generation of OLEDs emit by a process called thermally activated delayed fluorescence (TADF). The idea of the research project is to explore these and other organic semiconductors for use in lasers, thereby making a new class of laser. So far TADF materials have been developed and studied almost entirely for applications in OLEDs and displays. The requirements for lasers are related (e.g. light emission is required) but not identical. In particular all organic lasers tend to accumulate triplets which can then stop the laser action, leading to pulsed operation. Sometimes this problem is managed by putting in a material to remove triplets, but that also wastes their energy. In contrast we will explore TADF and other materials that can convert the undesired triplets into useful light emission providing a very interesting route to overcoming this problem. 

    The project will start in St Andrews, and the first major task will be to study the gain and triplet dynamics of candidate laser materials. This will involve measurements of transient absorption and transient luminescence. Distributed feedback lasers will then be made from promising materials and their dynamics studied. Research in Karlsruhe will include developing a rate equation model of laser operation. It will also use the Karlsruhe Nano Micro Facility KNMF. Furthermore, Karlsruhe Insititute of Technology (KIT) has an outstanding expertise in two-photon direct laser writing which not only gives a similar resolution to electron beam lithography but also enables 3D structures to be made.  

    At the end of the project we aim not only to have demonstrated high performance lasers made from TADF and related materials, but to have identified the key materials design considerations for TADF lasing and a validated rate equation model of TADF lasing that many groups will find useful for the development of these new devices. The research student will gain valuable knowledge and skills relating to lasers, photophysics, materials and nanofabrication.

    The project will be managed jointly between the School of Physics and Astronomy at St Andrews and the Karlsruhe Institute of Technology in Germany. The student will be supervised by Professor Ifor Samuel and Professor Graham Turnbull (University of St Andrews) and Professor Uli Lemmer (Karlsruhe Institute of Technology).

    Informal enquiries regarding this scholarship may be addressed to Professor Ifor Samuel – email [email protected] or Prof Graham Turnbull [email protected]

    How to apply

    Apply by 5th April 2024 at .

    Please indicate in your application that you wish to be considered for this Global St Andrews scholarship (reference Samuel).

  • World leading St Andrews PhD scholarship for a joint PhD project between the OSC and School of Medicine – apply by 15th April

    Project details

    This interdisciplinary project between the Schools of Medicine and Physics and Astronomy at the University of St Andrews explores new light sources for killing bacteria and other microbes.  We are looking for candidates either from a biological sciences/microbiology/medicine background or from a materials science/physics/engineering background.

    Photodynamic therapy (PDT) is a powerful tool that currently has applications in cancer treatment at the skin surface. Antimicrobial PDT (aPDT) is in its infancy but has great potential that must be explored, especially in the era of ever-rising levels of antimicrobial resistance (AMR).

    aPDT is similar to conventional PDT in that three elements are required: light, a light-activated chemical (photosensitiser) and oxygen.  The light source excites the photosensitiser, which in the presence of oxygen generates reactive oxygen species that kill undesired cells.

    Although PDT is used across the world, it has so far been limited by the need for large and specialized light sources, such as lasers.   We have shown that organic light-emitting diodes (OLEDs) – now widely found in mobile phone displays and televisions – can be used as light sources for PDT.  They are thin and potentially flexible, enabling convenient wearable light sources for medicine to be made.   In this project you will make OLEDs and explore their use for antimicrobial PDT, with particular emphasis on diabetic foot ulcers.  The project offers a unique opportunity to influence how antimicrobial treatment progresses into the future.

    According to the world health organization (WHO) survey in 2014, a total of 422 million people around the globe have been diagnosed with diabetes, and among the diabetic population the chances of developing foot ulcer are significantly high. A recent global epidemiology study shows that the prevalence of diabetic foot ulcer (DFU) in Belgium alone is 16.6% with an average of 6.3% in the world. Approximately 1 in 17 people in the UK has diabetes and around a quarter of them may develop foot ulcers at some stage. These ulcers are hard to heal even with specialist care, and in the UK only about half heal within 6 months, causing a huge burden on people with the disease, and many ulcers reoccur within a year of healing. Unfortunately, a substantial fraction (10-15%) of ulcers do not heal at all, leading to amputation of the toe, foot or affected limb and a drastic shortening of life.

    The aims of the project are:

    • To demonstrate that OLED PDT can kill the bacteria found in diabetic foot ulcers
    • Optimise treatment conditions for PDT of the bacteria in diabetic foot ulcers
    • Demonstrate that OLEDs are suitable for treatment of diabetic foot ulcers
    • Produce preliminary data that provides the basis for  a full clinical trial.

    As mentioned above, we expect an applicant to come from a biological sciences/microbiology/medicine background or from a materials science/physics/engineering background.  A successful applicant should be interested in learning about the other field, and would be required to learn the necessary skills in the field of study they are less familiar e.g. a microbiologist would learn to make OLEDs, and a physicist would learn to perform microbiology experiments.

    The student will be supervised by Dr Robert Hammond (School of Medicine) and Prof. Ifor Samuel (School of Physics & Astronomy).

    How to apply

    Apply by 15th April 2024 at World-Leading Scholarship 05 Medicine Physics Astronomy – Study at St Andrews – University of St Andrews (

  • View all our advertised PhD projects, funding information, and how to apply.

    We welcome applications from well-qualified candidates to study for a PhD.  We have  PhD projects available across our research activities, with topics ranging from materials physics to optoelectronic devices, and their applications including in biophotonics, sensors, and communications.

    View a list of all our advertised PhD projects 

    Please contact Prof. Ifor Samuel  or Prof. Graham Turnbull  to discuss further if you are interested.

    Further information on funding, and how to apply for a PhD at the University of St Andrews, is available on the School of Physics & Astronomy Postgraduate Research Courses page

  • Find current job opportunities in the research group.

    Please see below for any currently advertised research positions.
    No positions currently advertised. Specific open vacancies will be advertised here when they become available.

    Applying for an externally-funded independent Research Fellowship?

    We welcome enquiries from highly qualified candidates who are looking for a host department for a fellowship application, including for those funded by EPSRC, JSPSRoyal SocietyRoyal Academy of Engineering, Royal Society of Edinburgh, and The Royal Commission for the Exhibition of 1851.