PhD Opportunities

If you are considering applying for one of the PhD projects below, please feel free to contact the associated supervisor(s) for more information. Applying is relatively straightforward and can be done electronically. Some of the projects below have funding; others will require you to apply for funding from external sources. More information about available scholarships (for UK, EU and international students) can be found here.

Our department is proud to create inclusive student, research, and working cultures that are supportive and welcoming to those from all backgrounds, genders, ages, disabilities, religions, and other protected groups. We are committed to providing a postgraduate program that not only equips you with the technical and professional skills you will need in your career, but which is also enjoyable, supportive, diverse, and inclusive. We welcome all applications, but especially those from the under-represented groups in physics. Everybody’s needs will be supported, but if you do have any concerns, you can contact us, in confidence, to discuss how we can support your particular needs during a research degree at the University of Leeds.

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IOP Bell Burnell Graduate Scholarship Fund

The IOP Bell Burnell Graduate Scholarship Fund is for full or part-time graduates wishing to study towards a doctorate in physics and from groups that are currently under-represented in physics.

We have an internal deadline of 8th December 2021. You need to be interviewed and sent an offer letter by this date.

If you would like to talk to us about this scholarship then please email Mike Ries .

Watch this YouTube video from Jocelyn Bell Burnell herself, talking about this funding.

Find out more ›

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Centre for Doctoral Training in Soft Matter and Functional Interfaces

 

Up to 16 fully funded four-year PhD studentships per year are available for graduates in physical science subjects, food science, mathematics or engineering.
Find out more ›

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Developing a tuneable ferroelectric nematic materials platform

Supervisor: Dr. Richard Mandle

Nematic liquid crystals are ubiquitous in our lives; we encounter them constantly thanks to their widespread use in display technology. The nematic liquid crystal state is characterised by the constituent molecules being oriented, on average, along some direction termed the director. Even when formed from polar molecules, there is no preference for pointing “up” or “down” along this direction and so the bulk nematic phase is typically apolar.

Over a century ago, Max Born [1] speculated that a polar nematic fluid would exist if the molecular electric dipole moments are large enough that dipole-dipole interactions between molecules are sufficient to overcome thermal fluctuations. The push to develop apolar nematic liquid crystals in display technology, coupled with the absence of experimental proof of the existence of polar nematic phases, meant that Born’s conjecture was largely forgotten.

In 2017 two materials were reported – RM734 [2] and DIO [3]– that are now understood to have polar nematic order and are ferroelectric, over a century after Born’s conjecture [4-6]. This so-called ferroelectric nematic (NF) phase displays a host of unique properties that cannot be easily replicated by other fluid systems: ferroelectricity [5], polar domains [7], strong non-linear optical response [7], unique electrooptics [8], to name a few [9]. However, realizing these properties requires an improvement in materials and our understanding of how formulation relates to bulk properties.

This project is experimental in nature, with potential for supporting experimental work with modelling and simulations as required. This project will deliver an NF materials platform that enables any property of interest to be tuned, and thus will become the ‘standard’ material used in the field for the coming years. You will work with novel NF materials developed at the University of Leeds, formulate multi-component mixtures, measure physical properties, analyse data, and build an understanding of the physics of the NF phase. This project is most suited to candidates with a background in Physics, Chemistry or Materials Science.

1. M. Born, Sitzungsber. Preuss. Akad Wiss., 1916, 30, 614-650.
2. R. J. Mandle et al., Chem. Eur. J., 2017, 23, 14554-14562.
3. H. Nishikawa et al., Adv Mater, 2017, 29, 1702354
4. A. Mertelj et al., Phys Rev X, 2018, 8, 041025
5. X. Chen et al., PNAS, 2020, 117, 14021-14031.
6. R. J. Mandle et al., Nat Commun, 2021, 12, 4962.
7. N. Sebastian et al., Phys Rev Lett, 2020, 124, 037801.
8. C. L. Folcia et al., Liq Cryst, 2022, advance article
9. N. Sebastian et al.,, Liq Cryst, 2022, advance article

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Sustainable compostable packaging formed from all natural materials

Supervisors: Prof. Mike Ries and Dr. Peter Hine
Additional Supervisors: Dr Yoselin Benitez-Alfonso and Prof. Long Lin
Application deadline: Friday 22 July 2022

We live in a throw-away society in which we make, use, and dispose with detrimental effects to our environment and health, such as plastic contaminants in oceans and food chains. This is due to the industrialisation of many commercial processes, dramatically reducing the cost of products for consumers. These lower prices do not reflect the real cost to the environment of either their manufacture or their disposal. Over 40% of plastic packaging is discarded in landfills with almost one third being dumped illegally. A new paradigm is needed, a circular bioeconomy with waste reuse to generate products and energy. This project will turn materials obtained from agricultural waste with no current usage, tomato leaf and orange peel, into compostable films for packaging. The films will need the required mechanical properties, optical properties and compostability (Leeds Plant Growth Suite). As part of your PhD, you will link these properties to the structure/dynamics/orientation at a molecular scale (crystallinity, anisotropy, dynamics, composition). The materials will be studied using scanning electron microscopy, NMR, X-ray, FT-IR, optical microscopy, Raman spectroscopy, and Instron-tensile tests. This project will require a multidisciplinary approach, combining physics with biology and chemistry to unlock the full potential of these natural resources.

Industrialisation of manufacturing has dramatically reduced the cost of products for consumers. An unfortunate side effect is the throw-away society, a linear economy in which we “take-make-dispose”. Over the next decade a billion tonnes of oil-based plastic will be dumped into landfill and seep into our oceans, much from packaging. This plastic waste not only damages our environment, but also enters our food chain. A new approach is needed, a circular economy in which we eliminate waste and reliance on finite resources. This project will develop a new range of packaging materials, coated films that are biodegradable, formed from sustainable sources. These can then replace current conventional fossil-fuel based packaging. We need an economy built on carbohydrates not hydrocarbons; plant biopolymers are an inexhaustible renewable resource of molecules from which we can make materials, chemicals, and energy. This interdisciplinary project brings together academia with industry, Futamura Chemicals UK Ltd, to create a next generation of sustainable, all-natural, compostable packaging.

This project has the potential to radically change how packaging is produced in the UK and then across the world. It will help deliver cleaner growth by transforming waste into packaging, reducing our reliance on fossil fuels, and as the materials here produced are compostable, will reduce plastic waste entering the environment. The challenge in this project is to form cellulosic films with tailored film barrier properties from natural waste sources. We have identified tomato leaf and orange peel as these are “non-competitive waste streams”, with no natural home that are currently incinerated or sent to landfill. The films will need the required mechanical properties, optical properties, barrier properties and compostability.

This project will: quantify and understand the properties of the films produced from tomato leaf by Futamura; determine the effect of coating these films with orange peel derived formulations on barrier and mechanical properties; understand the relationship between film microscopic properties (composition / orientation / structure) and the resultant film macroscopic properties; and assess the compostability of the films (soil structure, chemicals released).

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The role of order and disorder in impact absorbing materials

Supervisors: Dr. Devesh Mistry and Dr. Paul Thornton (School of Chemistry)

The everyday world is full of mechanical shocks, impacts and vibrations that cause damage – we need new materials to protect against these.

Phone screens, cycling accidents, satellite launches and electric vehicle batteries – all examples where inadequate protection from mechanical forces can have healthcare, safety, product longevity and financial consequences. We need to develop new lightweight impact absorbing and vibration damping materials.

Conventional elastomeric materials (rubbers) have poor shock absorbing (dissipative) capabilities. However, one class of ordered elastomer, called a liquid crystal elastomer (LCE), show exceptional dissipative capabilities. The reasons for why LCEs have such excellent properties remains unclear. The chemical structures and molecular ordering present in these materials are evidently key factors, but precisely how these come together to give rise to highly dissipative materials is something we need to better understand from a polymer physics standpoint.

In this project you will create a range of ordered elastomeric materials and you will study their structure-property-processing relationships to understand the physics of their mechanical behaviours. You will start with LCEs, fabricating materials of various polymer chemistries, structures, and orders, and you will test their thermal and dynamic mechanical properties. From there you will explore different ordered polymeric materials such as block co-polymers and supramolecular proteins – all the time linking the physics of these different systems together.

This project is highly experimental in nature and will require you to work with chemicals to produce bespoke polymeric materials, to perform physical testing of these materials and to analyse data with a view to understanding the physics of the system. The project is therefore most suited to students from Physics, Chemistry, and Material Science backgrounds. Students from Engineering disciplines will be considered if they can demonstrate some relevant knowledge in areas such as polymers, soft matter, liquid crystals, mechanical testing and materials synthesis.

If you are interested in this project and would like to find out more about the research topic or the PhD program at the University of Leeds, then please contact the lead project supervisor, Dr. Devesh Mistry.

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High Speed Materials for Holographic Head-up Displays using Liquid Crystal on Silicon Spatial Light Modulators

Supervisor: Prof. Cliff Jones

The Soft Matter Physics group have been approached by a manufacturer of Head-up-display systems for the automatic industry, who wish to investigate faster liquid crystal modes in high resolution spatial light modulators. The company was attracted by the world-class facilities at Leeds working on Liquid Crystals, that combines both device engineering and materials’ physics. In this project, both materials and device aspects of the will be investigated.

The company manufactures Head-up Displays for Augmented Reality in the automotive sector. Their proprietary Holographic Engine uses Liquid Crystal on Silicon (LCOS) spatial light modulators (SLM) to form a projection system that is lower power, higher efficiency and more compact and durable than conventional LCD approaches. It allows image formation with ultra-high resolution in multiple perception planes. A key area for the company’s future research is optical improvements of the light engine using faster and higher resolution SLM. This will require investigation of novel liquid crystal modes using new types of liquid crystal operation not before used in LCOS.

The aim of the research project will be to design and optimise polar switching modes of liquid crystals that target LCOS application and the current system. It has previously been shown that flexoelectric switching of the chiral nematic phase provides optical modulation that is much faster than the 5ms switching of conventional nematics. Odd-spaced dimers, of the type that exhibit the Twist-Bend Nematic phase, have been used to induce far higher flexoelectric coefficients than those that occur in calamitic liquid crystals. Furthermore, other novel polar nematic phases based on spontaneous splay have recently been discovered, that have the potential to provide further enhancement that is of yet unexplored. However, obtaining the suitable high-quality alignment of the liquid crystal materials for this mode has proven unsuccessful and unproven for LCOS devices. The Leeds team has developed novel alignment methods based on nano-imprint lithography, embossing and patterned self-adhesion that promise to resolve this issue. Work is currently underway under the supervisor’s EPSRC Manufacturing Fellowship, to move these methods to sub-optical length-scales. These alignment approaches will be refined in this project to suit low-cell gap LCOS SLM and applied to the new flexoelectric materials being developed. Furthermore, the Leeds team has recently developed a novel analogue ferroelectric liquid crystal mode, based on vertically grating alignment. The use of sub-optical gratings for this mode suited to LCOS will be investigate, together with other polar liquid crystal effects, such as the electroclinic effect. Such modes are envisaged to help improve LCOS resolution operation, as well as speed.

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Terahertz-frequency adaptive optics, using nematic liquid crystals

Supervisors: Prof. Helen Gleeson, Dr Alex Valvanis (School of Electronic and Electrical Engineering) and Dr Andrew Burnett (School of Chemistry)

This project will develop the first adaptive optics for the terahertz (THz) band of the electromagnetic spectrum, using nematic liquid-crystal devices. The THz band lies between the infrared and microwave regions and represents a meeting between electronic and optical technologies. Although numerous potential applications for THz sensing exist, including atmospheric and space research, security and biomedical imaging, and industrial inspection, there has been limited practical use of THz systems outside specialised laboratories. One key reason for this is the poor availability of optical components to guide, control and manipulate THz radiation. Specifically, THz systems rely on large and complex assemblies of fixed metallic reflectors or polymeric lenses, which can only be adjusted using slow and power-hungry mechanical positioners. In this project, the student will develop an entirely new adaptive-optics (AO) approach to system control, in which the optical properties of compact optical components can be adjusted dynamically using a simple electrical bias. The student will develop a range of AO components and systems, using nematic liquid crystals devices (LCDs) —a technique that has had considerable success in infrared and visible optics. These materials are fluids consisting of rod-like molecules, which preferentially align with each other along their long axes, resulting in anisotropic optical properties that can also be adjusted by applying a bias voltage. Initially, the student will study the properties of LC materials, using broadband THz time-domain spectroscopy to characterise, catalogue and improve their performance in the THz band. The most successful materials will be used to construct AO devices, including variable waveplates and attenuators, and spatial-light modulators, the first of their kind in this spectral band, and use them to demonstrate advanced applications including dynamic beam steering and circular dichroism spectroscopy.

Terahertz-frequency (THz) systems operate between the infrared and microwave bands of the electromagnetic spectrum. As such, they represent a meeting of optical and electronic technologies and offer unique opportunities for sensing and imaging. For example, numerous important gas species have strong and distinctive THz spectral features and cannot be distinguished using conventional infrared or UV/visible techniques.This underpins future satellite missions and lab-based analytical techniques to investigate climate-change processes in the Earth’s upper atmosphere, or star formation processes in deep-space nebulas. THz systems also offer great potential for non-invasive (non-ionising) biomedical imaging, security screening and industrial inspection.Until recently, THz systems have been too large, complex,and power-hungry for satellite applications. Through support from UKRI, and the UK and European Space Agencies, researchers at Leeds have developed the first ultra-compact, waveguide-integrated THz sources based on quantum-cascade lasers, which are potentially suitable for use in satellite payloads. A significant challenge for practical system development remains though, in that THz optical components are very poorly developed compared with those in other spectral ranges. Adaptive optics (AO) is one sucharea in which THz optics fall far behind other spectral bands. AO systems contain components whose properties can be controlled dynamically to manipulate the wave front of an optical field. These enable, for example, automated image compensation for atmospheric turbulence, laser power stabilisation and beam-steering, dynamic polarisation control, or rapid single-pixel imaging. THz AO systems remain severely limited by the lack of suitable components. Specifically, the relatively short wave lengths of THz radiation (~100μm) introduce extremely challenging machining tolerances for the micro-electromechanical systems, deformable reflectors or micro-mirror arrays commonly used in millimetre-wave systems. Conversely, many materials used in infrared or visible optics are opaque at THz frequencies, and diffraction limits the use of microlens systems.In a recent UK Space Agency “pathfinder” project, we have demonstrated a novel and promising route toward THz AO systems, using nematic liquid-crystal devices (LCDs). These materials are fluids consisting of “rod-like” molecules, which preferentially align along one direction, giving different refractive indices and light-absorption along different axes. By applying an electrical bias, the alignment can be adjusted, resulting in dynamically controllable optical properties. This underpins a vast array of AO applications in the infrared and visible bands, including spatial-light modulators, controllable lenses and variable waveplates. We have developed, for the first time, devices that operate at frequencies well above 2THz, underpinning a potential step-change in THz AO systemcapability. In this project, the student will develop the first THz-AO systems based on nematic LCDs and demonstrate advanced applications in beam-shaping and spectroscopy that extend far beyond the use of static optics. Key objectives include the development of:

• High-performance LC materials for THz applications: The PGR will collaborate with industrial partners (Merck and RAL Space) to analyse and identifythe first LC materials with high birefringence and low loss at >2THz, using broadband THz time-domain spectroscopy. Results will feed back into the design of improved LC mixtures, and development of the first database of materials in this spectral range.

• The first variable LCD waveplates and attenuators at THz frequencies: Single-cell LCDs will be developed using low-loss THz electrodes and substrates, enabling dynamic control over the transmission of radiation. Structures will be optimised to explore the trade-off between speed and dynamic range of operation, allowing modulation of the transmitted power or switching between circular polarisation states at “video-rate” frequencies.

This project is available as one of five PhD studentships with the Bragg Centre to tackle fundamental and applied problems to create new and improve existing materials. These will address fundamental and applied problems across design, characterisation, fabrication and modelling.

The Centre comprises around 200 members from over sixteen Schools within the University of Leeds and has had continued investment in excellent facilities and infrastructure, including a new building opening in 2021, to ensure that our staff and students benefit from state-of-the-art, high quality equipment and laboratories. We are a founding partner of the Henry Royce Institute, the UK’s Institute for Advanced Materials.

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Towards the Electronic Nose with Liquid Crystal Droplets

Supervisors: Prof. Cliff Jones, Prof. Helen Gleeson and Prof. Richard Bushby .

Liquid crystals are a good example of the use of soft-matter in electronic device applications, often for displays but also in optical films, spatial light modulators, switchable lenses and an increasing variety of applications. One of the more promising applications is in sensing devices, where small levels of certain chemicals or biological species at the liquid crystal interface cause drastic changes to the arrangement of the liquid crystal. Often the liquid crystal is contained within spherical droplets and the molecular alignment is mediated by appropriate surfactants at the solvent (usually water) boundary. This has the advantage that the droplet size can be accurately controlled by micro-fluidic methods. However, other geometries will also be investigated, such as patterned surfaces where both the shape and surface properties are varied to control the arrangement of the liquid crystal.

To make an electronic or optoelectronic nose, the sensor needs to include an array of elements each sensitive to a different vapour. Liquid crystals have a variety of different phases, phase sequences and symmetries, offering the potential for a wide range of detectable responses. This work will begin by investigating the relationship between liquid crystal material, its phases and symmetry, the surface properties of the aligning layer and its containment design and the optical response to a variety of gases. Optical and electrical methods for detecting the changes will be considered with the aim of fabricating operating devices. The work is envisaged to be experimental in nature, but could be adapted to include a high theoretical content, depending on the successful candidate

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Vitrimers – a new class of materials for sustainable re-processable plastics and novel battery designs

Supervisors: Dr Johan Mattsson and Prof. Andy Wilson (School of Chemistry)

For many materials applications, so-called thermosets i.e. polymers with permanent inter-chain cross-links are the optimum choice due to their long-term mechanical and thermal stability. However, the presence of permanent cross-links makes these materials very difficult to process and almost impossible to effectively re-process and thus recycle. Thus, finding a route to produce polymers that behave like thermosets across their relevant operational temperature range, but which can be readily processed and are malleable above this temperature range, is key for moving towards more sustainable plastics and a more circular economy. This project is focused on a new class of supramolecular polymers, so-called vitrimers [1] which provide a solution to this problem.

Supramolecular materials are based on fundamental molecular units which cross-link to form networks. The cross-links impart physical properties such as mechanical rigidity and by controlling the nature of the cross-links, supramolecular materials can be designed with tuneable and switchable properties, where the trigger could include temperature, a catalyst, or an applied electric or magnetic field. Due to the nature of the chosen type of cross-link interactions, the number of cross-links is always fixed; this gives vitrimers unique properties. Typically, at low temperatures (relevant for a particular application) the cross-links stay intact and the vitrimer mimics a thermoset. At high temperatures, however, cross-link rearrangements allow material shape changes, which makes the vitrimers malleable and processable.

In this project, the link between the nature of the polymeric building-blocks, the cross-link interactions and concentration, and the resulting molecular motions and mechanical response will be systematically characterized for chosen model vitrimer systems. The project aim is to develop a proper understanding of these novel materials and use this understanding to devise design rules, which will help developing materials for practical applications. We are here particularly interested in the design of more sustainable, recyclable, polymers and the incorporation of vitrimers into the design of new types of solid state batteries. The vitrimer systems will be synthesized in Leeds and investigated using a wide range of experimental techniques including dielectric broadband spectroscopy, calorimetry, rheology, scattering (light, x-ray, neutron), and atomic force microscopy.

You will work with Dr. Johan Mattsson in the Soft Matter Physics Group in the School of Physics and Astronomy and Prof. Andrew Wilson in the School of Chemistry in Leeds. You will work in an international dynamic research environment characterised by close collaborations between experimentalists and theorists and an inspiring mix of fundamental and applied research.

[1] D. Montarnal et al., Science 334, 965 (2011)

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Engineering biomaterials through liquid crystal imprinting

Supervisor: Dr Mamatha Nagaraj

Liquid crystals are a fascinating soft materials that elegantly combine characteristics of the conventional solid and isotropic liquid. There are a number of liquid crystal phases and they show unique molecular arrangements and functionalities. The process of transferring of functionalities of liquid crystals into polymer matrices is called as imprinting. In this project you will work on creating and investigating imprinted structures of liquid crystals using biomolecules for applications in medicine and tissue engineering. The student will have the opportunity to learn a number of experimental techniques vital to soft matter physics such as polarizing optical microscopy, X-ray scattering, dielectric spectroscopy, device fabrication techniques and electron microscopies.

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Materials from nature: All Natural Composites

Supervisors: Prof. Mike Ries and Dr Peter Hine

Each year we produce 300 million tonnes of plastic waste, with 8 million tonnes entering our oceans and a staggering 100 million tonnes being dumped in landfill. Therefore, we need to develop alternative sustainable processing systems that can generate bio-based products with less environmental impact; all-natural-composites have the potential to replace synthetic plastics in a wide variety of applications. As these materials will be formed entirely from one natural material their recyclability is greatly simplified. This work will incorporate natural biopolymers such as cellulose, silk and keratin, to form a variety of all-natural-composites.

All polymer composites is a growing area of research and development in which the Leeds Soft Matter Physics group has been one of the foremost pioneers. Research to date, on melt processable polymer systems, has led to a number of major patents and via a University spin-off company, to commercial applications. In the view of replacing synthetic polymers by renewable matter, all-natural based composites have great potential. In this project we shall manufacture and study all-natural composites using “green” processing routes. Selective surface solvation of the biopolymer fibres, via environmentally friendly solvents such as ionic liquids, will be used. Preliminary studies (using flax, hemp and cotton fibres) have shown that excellent bonding can be achieved, but composite morphology and mechanical properties are not yet understood. The composition of the solvent (type of solvent and fraction of cosolvent), pre-activation of fibres (distilled water / caustic soda), the fibre type and hence properties (different biopolymer sources), the fibre arrangement (unidirectional, woven) and processing variables (solvation time, temperature and pressure) will be varied. The mechanical properties (tensile, bending, impact) of the composites will be studied and correlated with their structures (WAXS, NMR, SEM).

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The physics of glass – fundamental mechanisms and novel applications

Supervisor: Dr Johan Mattsson

The formation and behavior of glassy disordered non-equilibrium solids is one of the deepest unsolved fundamental questions in physics. Moreover, to better understand the physics of glassy materials is important for a wide range of technologies, for battery and other energy materials, pharmaceuticals, foods, paints and for our understanding of biological matter such as proteins and cells. The fact that neither the microscopic mechanisms involved in glass formation nor the behaviour of the glassy state is well understood makes this a key problem both within the fundamental and applied sciences.

This project will focus on using advanced experimental techniques to investigate the physics of glass-formation, with a particular focus on the effects of molecular topology, the introduction of specific interactions such as hydrogen bonding and the molecular response to high pressures and mechanical deformations. The molecular structure and dynamics will be investigated using techniques including advanced light, x-ray and neutron scattering, dielectric relaxation spectroscopy and calorimetry.

You will work in an international dynamic research environment characterized by close collaborations between experimentalists and theorists and an inspiring mix of fundamental and applied research. The project will also include significant international collaborations with leading international research groups.

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Developing novel mechanical metamaterials

Supervisor: Dr Mamatha Nagaraj

Nature uses unique mechanisms to produce robust architectures such as biological exoskeletons, bones and wood. The internal lattice architectures of these materials are responsible for the structures being simultaneously lightweight and exhibit outstanding mechanical properties. Inspired by nature, the research on lattice miniaturization has developed rapidly over recent years. Artificial nano-lattice materials find numerous applications in biomedical implants, load-bearing structures, fast charging and high capacity batteries, porous membranes and cancer therapy. The focus of this project will be to establish routes to fabricate intricate three dimensional nano-lattices using liquid crystals, polymers and colloidal dispersion and test their applicability as mechanical meta materials.

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Glasses controlled by light

Supervisor: Dr Johan Mattsson and Prof. Cliff Jones

The formation and behaviour of glassy disordered non-equilibrium solids is one of the deepest unsolved fundamental questions in physics. The constituent building blocks of a glass can be either small molecules or polymers and glassy materials are widely used in applications ranging from construction and energy materials, pharmaceuticals, medical technologies, foods and paints.

In this project you will explore different routes to controlling the properties of glass-forming materials by addition of, or functionalisaton with, light-sensitive molecules whose structure can be switched between different conformational states by the application of light. Recent work has demonstrated that inducing local perturbations can have significant effects on the molecular motions of the glass-forming material, for instance driving various relaxation modes and control molecular diffusion. The addition of light-sensitive molecules to glassy materials thus has the potential for design of novel glasses with physical properties controlled by light.

The project will use advanced experimental techniques to characterise the material behaviour, where the molecular structure and dynamics will be investigated using advanced scattering, dielectric relaxation spectroscopy, rheology and calorimetry.

You will work in an international dynamic research environment characterized by close collaborations between experimentalists and theorists and an inspiring mix of fundamental and applied research. The project will also include significant international collaborations with leading international research groups.

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Controlled self assembly of nanoparticles for photonic and plasmonic applications

Supervisor: Dr Mamatha Nagaraj

Self-assembly is a remarkable phenomenon in nature and developing novel self-assembled systems for new technology areas is both exciting and important. Examples of new systems include ones where nanomaterials have been dispersed in liquid crystals to enhance their physical properties and to achieve alignment and self-assembly of nanomaterials into large organized structures in different dimensions. Such systems are potentially important because of their unusual switching properties which could be exploited in devices including, optical switches and diffraction gratings, as well as their novel architectures that will interact with light (photonic structures). The focus of this project will be to develop novel functional materials by combining liquid crystals and nanomaterials. The student will work on uniquely grafted nanoparticles, which allow controlled assembly of nanoparticles into regular lattice structures, hence allow applications in photonics and plasmonics.

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The physics of microgels and other soft colloids

Supervisor: Dr Johan Mattsson

Transitions where a material goes from a fluid state to an arrested but still disordered state arise in a diverse range of systems (colloidal dispersions, molecular or polymeric fluids, granular systems, emulsions, foams, pastes, and biological cells). Colloidal dispersions made from ‘soft’ elastic microgels provide an excellent model system for such behaviour and are also industrially highly important. Microgels are used in applications including biosensing and medical diagnostics, in pharmaceutical delivery systems and switchable materials and are regularly used to control the rheological properties of industrial products such as paints, motor oils, foods, cosmetics and inks. Many applications of microgels are based on highly crowded states, but we presently have little understanding of the rich and fascinating behaviour that takes place in the packing of such soft colloids. This project is aimed at directly addressing key fundamental aspects of the physics of microgel dispersions where important open questions include how the motions of the microgel particles are correlated in time and space, how the motions, arrangements and rheology are affected by the individual microgel particle shape, elasticity (heterogeneity) and by the inter-particle interactions. An important component of the project is the use of the 3D-photon correlation light scattering set-up in Leeds, which will be combined with other light scattering techniques, microscopy and rheology as well as colloidal synthesis techniques to provide a full characterisation and control of these experimental systems

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