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Project Title: Planterary occulations with CHEOPS

Project Description:

The high precision photometry obtained from space-based instruments allows us to study the properties of close-in planets in details.  During occultations, we can measure the  flux drop observed as the planet goes (disappears) behind the star. Occultation observation of hot Jupiters are particularly interesting as these planets are tidally locked with the same hemisphere exposed to the star.  These observations reveal the brightness of the planetary day side, which corresponds to the planet's reflectivity or geometric albedo at optical wavelengths. Moreover, they can indicate the presence of clouds on the dayside. The CHEOPS space telescope performs occultation observations of hot Jupiters with excellent precision. 

The goal of this project is to analyse publicly available CHEOPS observations of a hot Jupiter: understand and reduce the data, fit model to the data to measure the occultation depth, and finally estimate the reflectivity and temperature of the planet's dayside. 

Project Title: Fluctuations in the non-equilibrium orbital angular momentum

Project Description:

Our group has related the orbital angular momentum (OAM) to a form of inter-band dynamics known as Zitterbewegung, and that in non-equilibrium systems it is associated with the establishment of a steady-state dipole, and that strong orbital angular momentum densities can be generated in spin-3/2 hole quantum wells. However, all of these findings rely on the expectation value of the OAM, and in small systems fluctuations may become important. The student will work on deriving a formula for the fluctuations in the OAM, applying it to known models in which the OAM density is known to be large, and determining when the fluctuations are important and what impact they would have on potential technological applications. 

Project Title: Quantum corrections to orbital dynamics and orbital currents

Project Description:

Our group demonstrated that the way the transport of orbital angular momentum (OAM) had been previously calculated was incomplete, and developed a new formula for determining the OAM current in an arbitrary crystal. At the moment this formula has only been applied to a few simple models. The student will work on applying this formula to a number of new materials where large responses are expected, for example ferroelectrics and Weyl semimetals, and understanding the origin of the OAM current in each material. 

Project Title: Distribution of the Magnetic Field of Atomic Electrons Inside the Nucleus

Project Description:

Recent breakthroughs in the accuracy of atomic spectroscopy have opened a new window for studying nuclear forces and searching for physics beyond the Standard Model in atomic experiments. This project aims to derive formulae for the distribution of the magnetic vector potential A(r) produced by relativistic atomic electrons inside the nucleus. The interaction between A(r) and the nucleon current density j(r) gives rise to the hyperfine structure of atomic energy levels, which has been measured with very high precision. Combining these measurements with accurate atomic calculations will make it possible to test modern nuclear models that predict the distribution of nuclear currents.

This project is based on relativistic electron wave functions obtained as solutions of the Dirac equation in a central field, together with quantum angular-momentum theory. A student undertaking this project will be expected to learn the necessary elements of the Dirac equation, relativistic atomic wave functions, and angular-momentum algebra independently under supervision. The project involves demanding analytical calculations and is suitable only for students with a strong background in quantum mechanics and electrodynamics, and who are confident in learning advanced theoretical material beyond the standard third year undergraduate curriculum and prepared to deal with technically challenging derivations.

Project Title: Exploring Galaxy Sizes with Deep Imaging 

Project Description:

Description: Galaxies do not have sharp edges; their light extends into faint outer regions that are difficult to detect. In this project, students will explore how galaxy sizes are defined and how deeper imaging reveals previously unseen structures. They will work with real data, learn basic data analysis techniques, and investigate the correlation between galaxy size and properties such as dark matter. The project will also demonstrate how observational limits can bias measurements. No prior experience is required. Students will start from scratch using Gnuastro, a simple and accessible data analysis tool offering a low-key alternative to Python.

Tasks:

1. Learn the main ways in which the size of a galaxy is defined, such as effective radius and isophotal radius, as well as alternative measures (e.g. R1). Understand the advantages and limitations of each method.

2. Explore galaxies observed with different imaging depths (e.g. SDSS vs. DECaLS) to identify how deeper data reveals faint outer structures.

3. Analyse surface brightness profiles and examine how light is distributed as a function of radius.

4. Estimate galaxy sizes from surface brightness profiles and compare results from different definitions.

5. Assess how imaging depth affects the inferred size of galaxies and discuss potential observational biases.

Project Title: Cosmic inflation and the origin of the large scale structure of the Universe

Project Description:

In this project you will explore the first moments of the Universe when cosmic inflation created the initial density perturbations that form the seeds of structure growth in the later stages of the Universe.  This will involve reviewing the theory background, computation of the statistical properties of the perturbations for particular inflationary models and inference from observations of the cosmic microwave background.

Project Title: Enabling high frequency measurements of large area quantum devices

Project Description:

Aim: Redesign build and test existing sample holders to allow RF (>50MHz) measurements of quantum devices in perpendicular magnetic fields

Supervisor: Dr. Isaac Vorreiter & Prof. Alex Hamilton

Students must be approved by supervisors before being accepted into project

Background: For qubit measurements, we have considerable experience using the QDevil daughterboard + motherboard system (shown below). However, this motherboard board is currently too bulky to mount it vertically within the probe. We have been able to mount it laterally, as shown below. However, we can then only apply an in-plane field. For Hall bar measurements, we need an out-of-plane magnetic field, making the current setup unsuitable. 

Tasks + Timeline:

(Based on a taste-of-research workload)

Discuss requirements: 1 week

Learn Altium: 1-2 weeks

Redesign motherboard: 3-5 weeks

Redesign daughterboard (optional): 3-5 weeks

Get PCB manufactured + delivered: 2-4 weeks

Order components: 1-2 weeks

Populate PCBs: 1-2 weeks

Test + verify PCBs (RT and in LN2): 1-2 weeks

Total time: 11 – 16 weeks

Main challenges:

Learning + understanding the different functionalities of the existing QDevil PCB

Determining the best PCB design to fit in attodry probe form factor

Ensuring reliable soldering of components, especially at cryogenic temps

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We gain the capability to perform Hallbar-like measurements in conjunction with RF reflectometry measurements for studying disorder in MOS systems – exciting stuff!

You’ll gain hands-on experience with PCB design using the industry-standard Altium software. You’ll also gain an appreciation and understanding for the cryogenic and circuitry requirements for our experiments.
Follow-up work would involve testing Hall bar devices, and lateral surface superlattice devices, to directly measure the quantum capacitance.

Relevant papers

1. Vigneau et al., “Probing quantum devices with radio-frequency reflectometry,” Applied Physics Reviews 2023.

2. L. A. Ponomarenko et al., “Density of States and Zero Landau Level Probed through Capacitance of Graphene,” Physical Review Letters 105, 136801 (2010).

3. Correlated insulator in the kagome flat band of a two-dimensional electrostatic crystal, DQ Wang, Z Krix, OA Tkachenko, VA Tkachenko, C Chen, I Farrer, ..., Nature Physics, 1-8

Project Title: III-V compound semiconductor nanowire for thermoradiative power generation

Project Description:

Supervisors: Peter Reece, Stephen Bremner (SPREE)

Semiconductor nanowires are part of a family of epitaxially-grown nanostructures, where size, shape and composition are controlled through a combination of growth conditions and surface patterning. They have many interesting properties that can be exploited to create functionality for device application and have found use across a wide range of fields, including integrated photonics, energy storage, environmental sensing, and quantum devices. From a physics perspective, the ability to control underlying electronic structure through geometry and composition is particularly useful for engineering specific material responses. 

In collaboration with the School of Photovoltaic and Renewable Energy Engineering, we would like to understand how nanowires might be used for enabling novel modes of energy harvesting, such as thermoradiative power generation or hot carrier collection. In the context of thermoradiative diodes, nanowires could be used to control the emissivity of the surface for improved radiative energy transfer, or to optimise electrical junction properties.

In support of this research, we will be setting up a micro-photoluminescence apparatus capable of measuring the light emission from nanowires under cryogenic conditions. This will be used as a basic characterisation facility for probing the optical and optoelectronic properties of nanowires grown in the ANFF Molecular Beam Epitaxy (MBE) facility.

Milestones:

Explain the main physical principles behind the thermoradiative diode and identify potential benefits of using nanowires for improving power conversion efficiency.

Experimentally characterise the important functional components of a custom-built laser scanning microscope.

Measure the temperature dependent photoluminescence from ensembles of nanowires and compare the results with an equivalent bulk semiconductor sample.

Measure the photoluminescence from a single nanowire at room temperature and compare the results with an ensemble measurements.

Project Title: Pentacene doped nanocrystals – new candidates for optically trapped magnetic resonance sensing Project Description:

Supervisors: Peter Reece / Adrian Mena / Dane McCamey

Optically detected magnetic resonance (ODMR) has gained recent prominence as a means of performing spatially resolved high sensitivity magnetometry. Detection of weak magnetic signatures at the micro- and nanoscales can be used interrogate many types of physical systems, from magnetoreception in biology, to low temperature electronic transport in condensed matter physics.

The most popular platform for performing magnetic resonance sensing is the nitrogen vacancy (NV) defect centre in diamond. This is a magneto-optically active defect centre, where the spin of the triplet state can be set and read using all-optical means. In our recent work we have been incorporating nanodiamonds with optical trapping and micromanipulation as a way of controllably deploying them to areas of interest within a complex microfluidic environment.

Beyond this diamond-based system, there are other interesting candidates for magnetic resonance sensing. A promising candidate is pentacene doped p-terphenyl (pc:ptp), a molecular spin system with triplet states that can be set and read optically. Molecular spins such as pc:ptp have gained interest recently as molecules can be chemically tuned and crystals can be made with a high density of spins.

In this project you will test the compatibility of pentacene doped nanocrystals with optical trapping techniques and compare their performance with commercial nanodiamond samples.

Milestones:

1.      Explain the basic principles of optical tweezers for nanoparticles and the methods used to quantify trapping characteristics.

2.      Use optical characterisation tools to perform optically detected magnetic resonance (ODMR) on pentacene doped para-terphenyl crystals and interpret the results in terms of the expected photo-dynamics of pentacene.

3.      Measure photoluminescence (and potentially ODMR) from optically trapped pentacene doped nanocrystals and investigate the influence of the infrared trapping laser on their optical properties.

4.       Compare these results with those obtain from optically trapped nanodiamonds, noting any similarities and differences.

Project Title: Artificial Electrostyatic Crystals on square lattice

Project Description:

Artificial crystals is a newest direction in research of quantum matter. The artificial nature of the crystals allows to engineer states of quantum matter that are impossible in the conventional chemical matter. This is important for fundamental research and for future possible applications.

In electrostatic artificial crystals the lattice structure is created by electrostatic potential imposed on twodimensional electron liquid.

We have recently published an experimental paper on artificial electrostatic crystal with triangular lattice where a new kind of Wigner crystal has been discovered1. The next step in this direction is the square lattice and this work is in progress. The square lattice is of a special interest since this case has a similarity with high temperature cuprate superconductors. The phenomenon of high temperature superconductivity had been

discovered 40 year ago and still remains an unresolved problem of quantum physics.

This is a theoretical project. The goal of the project is calculation of the band structure of electrons on artificial square lattice. This is the first theoretical step which is absolutely necessary for experimental studies.

The project will require some numerical computations, but not of a large scale. Knowledge of FORTRAN or C or C++ programming languages is necessary. Of course an excellent knowledge of quantum mechanics is also necessary.

Project Title: Uncovering the Milky Way’s History Through Nearby Galaxies

Project Description:

How did the Milky Way form, and how unusual is its history? To answer this, we compare our Galaxy with nearby “extragalactic cousins”: galaxies with similar properties that we can observe from the outside. In this project, you will join the 91ɫ��Ƭ-led GECKOS team and contribute to an international survey of 36 Milky Way-like galaxies. Using 3D spectroscopic data from the MUSE instrument on the Very Large Telescope, we can map how the stars move in each galaxy, measure their chemical composition, and search for faint clues left behind by past galaxy mergers. Students can work on projects involving imaging data, 3D spectroscopy, or mock observations built from galaxy models. These projects are data-intensive and involve Python programming, so some introductory coding experience is recommended.