Jake Xuereb

Research Projects

Whilst I do find myself meandering through quantum information and thermodynamics in fairly equal parts, the main line of research I am pursuing is thinking thermodynamically about well established quantum information protocols. Here I am trying to gain an understanding of two things; what fundamental relationships exist between classes of computational tasks and thermodynamic resources? And, what costs or limitations does thermodynamics impose on computation itself?
If you'd like to discuss these ideas or you'd like me to give a talk about related work please do reach out.
I am also happy to mentor undergraduate students interested in these topics, especially if you're a Maltese person making your first quantum steps.

(!) - We recently put up a manuscript on the arXiv that presents a framework which tries to attack these questions which we call the autonomous Quantum Processing Unit. This is an autonomous thermal machine formed of a quantum clock, computational target state and semi classical states that encode an algorithm one wishes to execute. We then present a time indepent interaction whose steady state is the desired computational output. This framework allows us to examine the thermodynamic cost of computation and how physics limits the speed of quantum computation.
- autnomous Qauntum Processing Unit : What does it take to construct a self-consistent model of quantum computation?
with Florian Meier, Marcus Huber and Pauli Erker. arXiv:2402.00111

Thermodynamics & Information Processing - By studying the manipulation of classical and quantum information through a thermodynamic lens I hope to understand what it means for a task to be complex and whether this corresponds to great thermodynamic work. I am trying to do this in the contexts of the compression of quantum information and quantum algorithms. A related project which I carried out during my Master's showed that estimating different traces of unitary matrices leads to different heat exchanges across a register of qubits.
- Deterministic quantum computation with one-clean-qubit model as an open quantum system
with Steve Campbell, John Goold, and André Xuereb. Phys. Rev. A 107, 042222

Energetic Cost of & Physical Constraints on Computation - Information theoretic ideas can be proven and discussed in way which is agnostic of the physics which would carry them out. But the protocols that instantiate these theorems involve physical processes, like measurements or unitary operations which can be spoiled by finite resources like imperfect clocks or hot control systems. Motivated by this, I am interested to know how physics limits our ability to perform computations and manipulate information, and what costs are incurred in trying to remedy these limitations. In a recent project, I have examined how the quality of clock an agent has access to limits their ability to perform quantum computations and cool quantum systems.
- The Impact of Imperfect Timekeeping on Quantum Control
with Paul Erker, Florian Meier, Mark Mitchison and Marcus Huber. Phys. Rev. Lett. 131, 160204
I gave a talk summarising this work at the TiQT 2023 Conference which you can watch here on Youtube.
A Popular Science article about this work you can check out is Imperfect Clocks Limit Quantum Computers on IEEE Spectrum.
- (!) Quantum Coding with Finite Thermodynamic Resources
with Tiago Debarba, Marcus Huber and Paul Erker we recently uploaded a work which investigate the thermodynamic resources required for an agent to compress messages of pure states. arXiv:2311.14561
I gave a talk summarising this work at the Quantum Resources 2023 Workshop in Singapore which you can watch here on Youtube.