Following a call for proposals in 2017, the third cohort of RIFP Fellows have been appointed and are starting the next stage of their careers at STFC and the Diamond Light Source. 10 Fellows will spend 2 years working on their chosen projects and benefiting from the available STFC and Diamond facilities and expertise.
The range of projects is very broad, and includes: technology development for accelerators such as RF-cavity and ion source design; synchrotron facility technology development for x-ray optics; studies of advanced materials such as frustrated magnetic systems and unconventional superconductors; understanding interfacial water in biosystems; neutrino physics studies; development of software for analysis of environmental and climate satellite data; development of techniques to study the inner solar heliosphere; and the effects of stellar radiation on interstellar gas clouds.
The individual projects are listed here.
|Fellow||Department name||Project title||Brief summary of project|
|Nilanjal Misra||ASTeC||Optimisation of Hybrid physical chemical vapour deposition (HPCVD) for Superconducting Radio Frequency (SRF) cavity||
Radio frequency (RF) cavities find applications in linear particle accelerators and have traditionally used Niobium as the preferred material. But for further improvements in cavity performance and to cut down on the cost factor, further innovation is imperative and alternatives need to be explored. The aim of the proposed project is to deposit novel alloy-based superconducting thin films on 3D geometry substrates to engineer highly efficient RF cavities with excellent structural and superconducting properties. A unique hybrid physical chemical vapor deposition (HPCVD) which combines both physical (PVD) and chemical (CVD) vapor deposition techniques will be employed for the purpose. This approach will nullify the disadvantages encountered while using either PVD or CVD individually for carrying out deposition reactions. The combined approach will facilitate alloy formation reactions to occur at much lower temperatures, which are conducive for using Copper as the cavity material instead of expensive metals such as Niobium. This project therefore seeks to expand the scope of HPCVD process in the field of commercially viable RF cavities that possess superior RF properties. We also propose to systematically study important plasma parameters and investigate plasma chemical species (ions, neutrals, radicals) and their energy distributions using suitable plasma diagnostic tools.
|Saumya Mukherjee||Diamond Light Source||Physics of pyrochlore iridates in strained thin films||
Electrons possess two important degrees of freedom, spin and orbital momentum, which are weakly coupled in most solid state materials. However, the strength of the spin-orbit coupling increases as the fourth power of the atomic number, and for 5d elements such as iridium, this coupling is large enough to compete with electron-electron correlations and crystal field effects. Most iridium oxides (iridates) have been studied in bulk form and represent a new class of materials known as spin liquids. We propose to study how epitaxial strain in recently-available thin films modifies the electronic and magnetic properties of several pyrochlore iridates. By tuning the competition between the spin-orbit coupling, exchange interaction and crystal field using strain we aim to realise new exotic states of matter, such as the Weyl semimetal phase, and show unconventional magnetic properties at low temperatures. This studies will act as a doorway for developing quantum spin liquid materials with unique properties linked with quantum computation and spintronics. In addition, the understanding of the strain induced exotic magnetic ordering in these materials will lead to realisation of new ground states such as novel topological phases.
|Vishal Dhamgaye||Diamond Light Surce||Development of Wavefront Correctors for X-ray optics||
A upward trend in obtaining highly brilliant X-ray beams from modern synchrotron radiation sources and free electron lasers is making it essential to make advanced research in X-ray optics. Increasingly, nanosized beams much smaller than 100nm are required with a strong interest to get to sub-10nm beam sizes. However, the X-ray Optics required to achieve this is beyond the present-day fabrication technologies. Invariably, residual fabrication errors, even if tiny, prevent achievement of ultimate small focused beam sizes. The aim of this project is to develop refractive corrective optics that when used in tandem with the imperfect optics compensates the residual fabrication errors to generate a near perfect optical system. X-ray optical elements based both on mirrors and lenses would be corrected. The development of refractive correctors is a multi-disciplinary activity and would involve several high skilled steps including precision metrology, advanced optics simulations, precision fabrication and accurate measurements at Diamond. The end-result would be the development of optical systems which will provide sub-100nm beams with the potential of eventually providing sub-10nm X-ray beams on Diamond beamlines. This new cutting edge technical development would be invaluable for the projected upgrade of Diamond to Diamond-II.
|Deepak Singh||ISIS ISIS Neutron and Muon Source||Muon studies of unconventional superconductivity||
Unconventional superconductivity is proclaimed to have the potential to be a key enabler for sustainable living due to its prospect to transport energy without losses, large energy storage key for renewable energy and spintronics. There are different classes of superconductors, which show unconventional superconducting properties. These properties are responsible for a wide variety of technological applications of superconductivity. One of this class of unconventional superconductor is non-centrosymmetric superconductor (NCS). They have been known for decades but became a prominent research topic with the discovery of the heavy-fermion superconductor CePt3Si, owing to its exotic properties. The mixed spin-singlet/triplet states were held responsible for most of the exotic properties in these systems, which theoretically depends on antisymmetric spin-orbital coupling (ASOC). Many strongly and weakly correlated NCS systems have been studied so far, still the mystery of ASOC in their pairing mechanism remains unresolved. There is also a possibility that some other parameters may also be involved in controlling the mixing, for example, electron correlation, but to date no substantial growth has been done in this regard. Therefore, the central theme of the project is to study how the interplay of ASOC and electron correlations determines the unconventional superconducting properties in NCSs.
|Jose Martinez-Gonzalez||ISIS Neutron and Muon Source||Understanding the Interface between Water and Biomaterials: Combining Neutron Scattering and in-silico studies||
Understanding the interactions between water and the surface of biomaterials is fundamental, for understanding wettability phenomena, adhesion of proteins or tissue regeneration around implant. Water in contact with the surface, so-called interfacial water, has attracted plenty of interest for many years. The properties of interfacial water are dependent on the specific interactions with the biomaterial, and typically result in significant changes to bulk state, such as the prevention of ice formation, water remaining in a glassy state below the freezing point of water. This project wants to improve the knowledge of the properties of this interfacial water using a combination of experimental and theoretical approaches. A new humidity cell that allows the characterisation of the growth of the different solvation layers of water using neutron scattering experiments will be developed. In parallel molecular dynamics simulations of biomaterials will be carried out, to obtain an atomistic view of the interface. Experiments and simulations combined provide a strong way to improve current water models and force-fields that define the interactions between the materials. From a wider impact, the outcome of this project should help improve material development for industries involved in water-based nanotechnology, medical devices and biosensors.
|Olli Tarvainen||ISIS Neutron and Muon Source||A maintenance free ion source for ISIS operations||
The ISIS neutron and muon source allows the study of materials on the atomic scale serving both scientific and industrial purposes. The neutron production at ISIS is based on accelerating a beam of hydrogen nuclei to 800 MeV energy and directing it into a metal target. The particle beam starts its journey through the accelerator from an ion source producing negatively charged hydrogen ions. The present ion source technology used cannot reliably deliver beam for periods longer than a few weeks and consequent source maintenance results in downtime for the whole neutron source facility. A planned upgrade of the particle accelerator will increase its efficiency by reducing the amount of beam lost in the early stages of the machine. Combined with other improvement in transporting the beam this means that the ion source will not have to produce quite as much current as before, which opens the door to using alternative ion source technologies. The project aims to develop a new radiofrequency (RF) H- ion source for ISIS operations with a lifetime in excess of one year. This improves the reliability and availability of ISIS and saves money.
|Harri Waltari||Particle Physics Department||Probing neutrino dynamics via sneutrino searches at the CMS experiment||
My plan is to study ways to detect sneutrinos at the Compact Muon Solenoid (CMS) experiment of CERN and how to use sneutrinos to probe neutrino dynamics. Sneutrinos are the superpartners of neutrinos, predicted by supersymmetry. Unlike neutrinos, they can give visible signatures at colliders. I shall study the options of sneutrino production mediated by a Higgs boson or some currently unknown heavier particle, which will decay to sneutrinos. The results will allow us to constrain neutrino models and give us an understanding of how neutrino masses are generated. The analysis strategies can also be used in future hadron colliders.
|Thomas Schuh||Particle Physics Department||CMS Track Trigger||
To fully exploit the physics discovery potential of the LHC the High-Luminosity operation is planed from 2026. The luminosity increase by roughly one order of magnitude beyond the original design imposes significant upgrades for accelerator and detectors. To cope with this high luminosity operation CMS will perform major upgrades to its detector. One element of this will be the complete replacement of the Silicon tracker with one of a novel design that will enable the fast reconstruction of tracks in hardware.
The “CMS Track Trigger” that this detector will enable, is a novel part of the first level trigger. The trigger makes the key decision of whether to record the results of an interaction for further processing. Interesting events are infrequent and the overall trigger system must reduce the event rate by a factor of 10 000. To enable this the Track Trigger has to perform the sophisticated task of track reconstruction within a time window of 4 μs and has to face an incoming data rate about hundreds of Tb/s. These requirements makes the CMS Track Trigger to one of the most challenging and most complex real time systems in the world.
This project will develop the hardware and firmware system for realising the Track Trigger in the latest cutting-edge technology. It will involve the design of ATCA boards utilising high speed FPGAs and the design and implementation in firmware of the data flow structure and the algorithms required to realise the track trigger system. The project will greatly benefit from the physics expertise at RAL that will help gauge the trigger performance and requirements.
|Oyuki Chang||RAL Space||Assessing the capabilities and limits of IPS analyses to describe inner-heliospheric structures||
Interplanetary scintillation (IPS) originates from variations (“twinkling”) in radio signals received from distant, compact radio sources on the sky as the radio waves travel through interplanetary space due to density changes in the outflowing plasma. IPS allows us to infer the speed and density of the plasma, two key parameters of the inner heliosphere. There are two primary sets of analyses that provide IPS solar wind speed determinations: Single-Station Analysis model (SSA), and multi-station Cross Correlation Function (CCF) analysis. Both of these operate on amplitude-scintillation data (amplitude changes). In order to combine and complement observations of IPS for better coverage, it is important to validate results and methodologies of the two techniques. This project aims to understand the capabilities and limitations of each technique to describe the solar wind structures using observations of IPS from radio telescopes such as the Low Frequency Array (LOFAR), the European Incoherent SCATter (EISCAT) radar, and the Multi-Element Radio-Linked Interferometer Network (MERLIN). Using the SSA model, it is possible to further explore parameters such as turbulence and anisotropy of the plasma, and in this way it is possible to complement each technique’s information to obtain a better description of solar wind structures.
|Megan Reiter||UKATC||Things fall apart: testing the role of photoiosing radiation in molecular cloud destruction||Most stars (and thus most planets) do not form in isolation; instead they are born in giant clouds of gas and dust where stars of both low- and high-mass form alongside each other. How these natal clouds are destroyed remains an open question, but it is clear that energetic radiation from the brightest stars plays an integral role. Recent numerical models suggest that this radiation rearranges cloud material, sculpting a few large structures and clearing channels for the rest of the material to be blow away. I will test whether this type of feedback is the primary agent of cloud destruction. To do so, I will use state-of-the-art data from the Hubble Space Telescope and the Multi-Unit Spectroscopic Explorer to measure the direct impact of stellar radiation. I will compare this to the motion of the remaining gas in the cloud measured with unprecedented resolution using the Atacama Large Millimeter/Submillimeter Array. combining these views allows me to determine whether the radiation of the brightest starts dominates the destruction of their birthplaces, and thus the cradle of most planets.|
Last updated: 24 August 2018