Industrially Co-Supervised Projects

See below for a list of 2025 industrially co-supervised and co-sponsored PhD projects.

Experimental Projects

QMO2501: Spin qubit shuttling in silicon quantum processors

Location: Quantum Motion (London)
Employer Supervisor: Fernando Gonzalez-Zalba
UCL Supervisor: John Morton

Quantum computers promise to solve computational problems intractable for classical machines. To be able to run these algorithms, modern quantum computing hardware needs to be scaled up. Silicon-based approaches to building a scalable quantum processor offer advantages such as high qubit density, record qubit coherence lifetimes for the solid state, and the ability to leverage the advanced nanofabrication methods of CMOS technologies.

This PhD topic will cover the design and measurement of silicon spin qubits based on quantum dots (QDs). Particularly, the project will focus on one of the key elements of a scalable quantum processor: spin shuttling modules to coherent connect different quantum processing units. The student will work towards demonstrating coherent spin shuttling over long distances, linking up quantum processors placed in a two-dimensional arrangement. There will be opportunities to learn about advanced nanofabrication techniques, fast readout and coherent control of qubits all performed at millikelvin temperatures in dilution refrigerators.

We are looking for:

Master level student 2.1 and above from top universities
Natural Science or Engineering background
Experience in a laboratory setting
Experience in programming
Able to work in a group
Excellent communication skills

QMO2502: Development of automated tune up for arrays of quantum dots

Location: Quantum Motion
Employer Supervisor: David Wise
UCL Supervisor: TBC

A quantum chip does not come into the world able to perform all the functions of a quantum computer. Considerable effort is required to tune a chip made of quantum dots so that they can act as qubits.

As the number of qubits increases, the process of tune up becomes more complex, so that the tune up must be performed without human intervention. Considerable progress has been made in the automated tune up of superconducting quantum chips. In chips based on quantum dots in silicon, automation is currently less well developed.

This project focuses on developing automated tune up for arrays of quantum dots to function as a quantum processor while minimising the number of sensors, to maximise the chip’s computational power. We have performed key proof-of-concepts demonstrations showing automation on small scale systems, however, tune up routines that can operate on a large number of qubits per sensor are yet to be demonstrated. This project will develop and demonstrate such routines, working with the Intelligent Automation and Quantum Hardware teams at Quantum Motion.

The project will involve significant programming in python, so a strong interest and background in scientific software development is essential. As developed routines will be used by experimentalists in the course of their work, an interest in good coding practice and usable software is highly desirable.

Techniques employed will include heuristics, machine learning, Bayesian optimisation and Hamiltonian learning. Some experience in these areas will prepare the student for the project, but a keen interest and desire to learn is more vital.

There will be opportunities to work closely with the hardware teams at Quantum Motion. An interest in working in the lab will be an asset.

OIO2501: Connecting qubits by shuttling: qCCD architectures with trapped ions

Location: Oxford Ionics (Oxford)
Employer Supervisor: Clemens Matthiesen
UCL Supervisor: TBC

Large-scale trapped-ion quantum computers may be realised by shuttling and reordering ions on a complex microfabricated trap, an approach known as the quantum-CCD (qCCD). So far, qCCD systems in simple trap topologies, e.g. small linear or loop traps, have been demonstrated in experiments with a handful of ions.

This PhD project explores experimental implementations of shuttling-based qubit connectivity architectures, which involves designing and implementing advanced qCCD architectures with non-trivial topologies, including junctions and closed loops, to explore aspects of

how these building blocks can be put together to build large and efficient computers, e. g. considering control systems, signal routing and multiplexing,
how architecture choices and operational constraints limit performance - considering primarily speed and fidelities, and
how NISQ algorithms can be executed in such a device.

We find the most successful candidates have a physics, computer science, or mathematics background - we look for raw ability to learn, and ability to reason about complex systems; we often find this well correlated with skill and experience in software development or designing, conducting and analysing experiments. This project entails experimental and non-experimental work.

OIO2502: Integrated ion-trap technologies for large-scale quantum computers

Location: Oxford Ionics (Oxford)
Employer Supervisor: Clemens Matthiesen
UCL Supervisor: TBC

Truly large-scale trapped-ion quantum computers with many thousands of logical qubits require application of many thousands of control signals - optical for state preparation, readout and cooling, AC and DC electric and magnetic fields for coherent qubit control - targeting individual qubits.
Current approaches involving, for instance, free-space optics independent of the ion trap chip, or connecting external signal generators separately to each trap chip electrode, do not scale to large numbers of qubits. Practical realisation of large quantum computers hinges on the development of ion trap quantum processing units (QPUs) that both

allow integration of all control signal delivery, and,
can be fabricated reliably and at scale,

while satisfying exacting standards on materials or surface properties required to perform high-fidelity quantum operations.

This PhD project focusses on developing, validating and benchmarking technology for fully integrated QPUs that optimise the performance of Oxford Ionics’s patented electronic qubit control.

TSO2501: Semiconductor quantum light sources at telecom wavelength for quantum communication networks

Location: Toshiba Europe Limited
Employer Supervisor: Andrea Barbiero
UCL Supervisor: Paul Warburton

Quantum networks, where information is encoded in single and entangled photons and transmitted over long distances through optical fibre, have the potential to transform secure communication and distributed quantum computing. New hardware based on semiconductor quantum dots (QDs) can enable this vision, thanks to the ability to generate single and entangled photons at telecommunications wavelengths.

However, quantum network applications demand efficient photon extraction, strong photon-photon interactions, faster emission rates, and scalability of fabrication. The combination of all these desirable features is challenging and has not been reported so far.

The project will be based at Toshiba Europe Limited in Cambridge, and will explore integration of QDs in nanophotonic devices for quantum network ready photon emitters. Experiments will first focus on the design, fabrication, testing and optimisation of semiconductor nanophotonic devices, followed by integration into fibre-connected systems and quantum networks. The student will be part of an experienced and supportive team of scientists, with daily supervision and the chance to interact with external partners in industry and academia.

We are seeking passionate applicants holding (or expecting to receive) a first-class or upper second-class degree in Physics, Electronic Engineering, or a similar subject. A background in optics, semiconductor physics, or quantum physics is preferable. Candidates should demonstrate familiarity with a programming language for data analysis (e.g. MATLAB or Python) and the desire to work collaboratively in a multidisciplinary team undertaking cutting-edge experimental research.

Non-experimental Projects

OIO2503: Quantum computing with OMG-type trapped-ion qubits

Location: Oxford Ionics (Oxford)
Employer Supervisor: Clemens Matthiesen
UCL Supervisor: TBA

The ability to encode different qubit modalities in the complex level structure of atomic qubits - in long-lived Optical transitions or Metastable states, or in the Ground state (the OMG architecture) - opens up new ways to execute quantum algorithms with atomic-based quantum computers. Coherently shifting between the qubit encodings circumvents fundamental cross-talk challenges in operating large-scale quantum computers, which for atomic qubits arise from the laser-driven cooling, state preparation and readout operations, where light scattering at the single-photon level can destroy the state of neighbouring qubits. These advantages come at the cost of increased complexity associated with the respective characteristics of the OMG qubit types.

In this PhD project, we will realise novel OMG-type schemes with trapped barium ions in scalable ion chip traps, with a focus on fundamental limitations of individual qubit operations and quantum algorithms with dozens of qubits.

OIO2504: Resource-efficient calibration, benchmarking and operation of next-generation trapped-ion quantum computers

Location: Oxford Ionics (Oxford)
Employer Supervisor: Clemens Matthiesen
UCL Supervisor: TBC

The performance of a real-life quantum computer is not just determined by the number of qubits and the gate fidelities but depends sensitively on details of how algorithms are run on it. We have to consider aspects ranging from how we map an algorithm to physical operations on individual qubits (i.e. compilation) given the particular hardware features (native gate operations, qubit connectivity, trade-offs between error rates, implemented quantum error correction codes…) to how the physical qubit environment is calibrated while running the algorithm.

This PhD projects explores themes around optimal operation of trapped ion quantum computers at Oxford Ionics, considering hardware and control architecture for near-term and future devices. The project has a strong theory component but includes validating and iterating on concepts using real hardware.

PCR2501: Quantum algorithms for many body Green’s functions

Location: Phasecraft Limited
Employer Supervisor: Raul Santos Sanhueza
UCL Supervisor: TBC

Many body Green’s functions (MBGFs) are a very useful tool to understand the behaviour of physical and chemical systems, and are directly measurable in experiments like angle resolved photo emission spectroscopy (ARPES). To approximate them using a quantum algorithm, they necessitate time evolution and ground state preparation, making them difficult to obtain in the near term, where only modest circuit resources are available. This project aims to develop strategies to lower the resource costs to approximate these quantities on near term quantum devices. Specifically using the structure of these quantities in the complexified frequency space, it has been shown that constant depth circuits (in the evolution time) can be used to approximate their signal, but suffer from instabilities with respect to sampling noise [1], inherited from the subspace expansion methods [2]. This project will investigate strategies to control these instabilities and extend these results to produce approximations closer to the real frequency axis.

[1] Approximating dynamical correlation functions with constant depth quantum circuits
Reinis Irmejs and Raul A. Santos
https://arxiv.org/pdf/2406.03204
[2] A Theory of Quantum Subspace Diagonalization
Ethan N. Epperly, Lin Lin and Yuji Nakatsukasa
https://doi.org/10.1137/21M145954X

A good, motivated student with background in physics, mathematics or computer science. Familiarity with concepts in condensed matter, materials science and/or Quantum information is desirable.

PCR2502: Fault-resilient quantum algorithms

Location: Phasecraft Limited
Employer Supervisor: Toby Cubitt
UCL Supervisor: Lluis Masanes

The biggest current obstacles to practical quantum computation are errors and noise. Although we have known since the 1990s that, theoretically, fault-tolerant quantum computation provides a solution, the overhead in terms of the number of gates and qubits is prohibitive. Thousands or of qubits and gates would be required to implement even a single fault-tolerant gate. Recently, I showed that there are certain quantum algorithms that are inherently fault-resilient: the output is guaranteed to be close to the correct state even in the presence of noise and faulty gate implementations, but without requiring any overhead. Currently, the known fault-resilient algorithms are not practical. The aim of this project is to develop the nascent theory of fault-resilient algorithms, and apply it to practical algorithms that would be suitable for implementation on current or near-term quantum computing hardware.

Strong background in theoretical physics, theoretical computer science, or mathematics.

RIV2501: Designing quantum error correction protocols under realistic hardware assumptions

Location: Riverlane
Employer Supervisor: Gyorgy Pal Geher (Staff Quantum Scientist) and Earl T. Campbell (VP of Science)
UCL Supervisor: Dan Browne

Building qubits is an extremely difficult engineering task. However, most quantum error correction (QEC) research tend to idealise the hardware and ignore the constraints it poses. Such constraints include connectivity, i.e. between which qubit pair one can apply an entangling gate and limits on the access to long-range connections, etc. Theory and experiment must converge together in the long term to make quantum computing a reality. Therefore, we dedicate immense effort into designing quantum error correction protocols that can be executed on realistic/feasible hardware. The PhD project’s focus will be to design such protocols generalizing recent breakthroughs such as Floquet codes and the hexagonal surface code. This will include designing fault-tolerant circuits for known QEC codes that fit on a given hardware, and to think about fault-tolerant computation. Since Riverlane works with several hardware partners, there is a potential opportunity to try out some of these new protocols on real qubits.

The ideal student would

Quickly acquire an understanding of CSS codes and the stabilizer formalism,
Quickly acquire an understanding of QEC codes, such as surface code, colour code, etc.,
Have an inclination for applying abstract ideas to real-world problems,
Have some coding experience in Python, or is willing to learn it (a major part of the project is coding and performing simulations),
Can effectively communicate in English.