What is quantum error correction? Find out in my review paper, Quantum Error Correction: An Introductory Guide. Now published in Contemporary Physics. An open-access version can be downloaded from the arXiv.

Welcome to my website! I work at the UK's newly established Quantum Software Lab where I lead research into quantum error correction.

Career

Current: Quantum Error Correction Lead, Quantum Software Lab, University of Edinburgh
2021-2023: Postdoctoral Researcher in Quantum Computing, Freie Universität Berlin
2018-2021 Research Associate in Quantum Error Correction, Sheffield University
2015-2018: PhD Quantum Computing, Durham University
2013-2014: Physics, University of California, Santa Barbara
2011-2015: MPhys Physics, Manchester University
2010-2011: Year in Industry, Shell Global Solutions

My research

Quantum computers promise to be vastly more powerful than the current generation of computers. However, there are many problems to be overcome if they are ever to become a reality. One of the principal hurdles is that quantum bits (qubits) are typically realised through fragile quantum systems such as single ions, photons or superconducting circuits. These systems are extremely difficult to control and are therefore susceptible to error. My research focuses on developing quantum error correction protocols designed to mitigate the effects of these errors.

Publications

The full list of my publications can be found on the arXiv or via my Google Scholar profile.

  1. Hardware-tailored logical Clifford circuits for stabilizer codes.
    Eric J. Kuehnke, Kyano Levi, Joschka Roffe, Jens Eisert, Daniel Miller.
    Preprint arXiv:2505.20261. Uploaded: 2025-05-26. arXiv: 2505.20261. doi: 10.48550/arXiv.2505.20261.
  2. Engineering CSS surgery: compiling any CNOT in any code.
    Clément Poirson, Joschka Roffe, Robert I. Booth.
    Preprint arXiv:2505.01370. Uploaded: 2025-05-02. arXiv: 2505.01370. doi: 10.48550/arXiv.2505.01370.
  3. Computing Efficiently in QLDPC Codes.
    Alexander J. Malcolm, Andrew N. Glaudell, Patricio Fuentes, Daryus Chandra, Alexis Schotte, Colby DeLisle, Rafael Haenel, Amir Ebrahimi, Joschka Roffe, Armanda O. Quintavalle, Stefanie J. Beale, Nicholas R. Lee-Hone, Stephanie Simmons.
    Preprint arXiv:2502.07150. Uploaded: 2025-02-10. arXiv: 2502.07150. doi: 10.48550/arXiv.2502.07150.
  4. Domain Wall Color Code.
    Konstantin Tiurev, Arthur Pesah, Peter-Jan H. S. Derks, Joschka Roffe, Jens Eisert, Markus S. Kesselring, Jan-Michael Reiner.
    Physical Review Letters 133 (2024). Published: 2024-09-13. arXiv: 2307.00054. doi: 10.1103/PhysRevLett.133.110601.
  5. An almost-linear time decoding algorithm for quantum LDPC codes under circuit-level noise.
    Antonio deMarti iOlius, Imanol Etxezarreta Martinez, Joschka Roffe, Josu Etxezarreta Martinez.
    Preprint arXiv:2409.01440. Uploaded: 2024-09-02. arXiv: 2409.01440. doi: 10.48550/arXiv.2409.01440.
  6. Localized statistics decoding: A parallel decoding algorithm for quantum low-density parity-check codes.
    Timo Hillmann, Lucas Berent, Armanda O. Quintavalle, Jens Eisert, Robert Wille, Joschka Roffe.
    Preprint arXiv:2406.18655. Uploaded: 2024-06-26. arXiv: 2406.18655. doi: 10.48550/arXiv.2406.18655.
  7. High-threshold, low-overhead and single-shot decodable fault-tolerant quantum memory.
    Thomas R. Scruby, Timo Hillmann, Joschka Roffe.
    Preprint arXiv:2406.14445. Uploaded: 2024-06-20. arXiv: 2406.14445. doi: 10.48550/arXiv.2406.14445.
  8. Analog Information Decoding of Bosonic Quantum Low-Density Parity-Check Codes.
    Lucas Berent, Timo Hillmann, Jens Eisert, Robert Wille, Joschka Roffe.
    PRX Quantum 5 (2024). Published: 2024-05-30. arXiv: 2311.01328. doi: 10.1103/PRXQuantum.5.020349.
  9. Graphical structures for design and verification of quantum error correction.
    Nicholas Chancellor, Aleks Kissinger, Joschka Roffe, Stefan Zohren, Dominic Horsman.
    Quantum Science and Technology 8, 045028 (2023). Published: 2023-10-01. arXiv: 1611.08012. doi: 10.1088/2058-9565/acf157.
  10. Correcting non-independent and non-identically distributed errors with surface codes.
    Konstantin Tiurev, Peter-Jan H. S. Derks, Joschka Roffe, Jens Eisert, Jan-Michael Reiner.
    Quantum 7, 1123 (2023). Published: 2023-09-26. arXiv: 2208.02191. doi: 10.22331/q-2023-09-26-1123.
  11. Bias-tailored quantum LDPC codes.
    Joschka Roffe, Lawrence Z. Cohen, Armanda O. Quintavalle, Daryus Chandra, Earl T. Campbell.
    Quantum 7, 1005 (2023). Published: 2023-05-15. arXiv: 2202.01702. doi: 10.22331/q-2023-05-15-1005.
  12. Towards practical quantum LDPC codes.
    Joschka Roffe.
    Quantum Views 5, 63 (2021). Published: 2021-11-01. doi: 10.22331/qv-2021-11-30-63.
  13. Single-Shot Error Correction of Three-Dimensional Homological Product Codes.
    Armanda O. Quintavalle, Michael Vasmer, Joschka Roffe, Earl T. Campbell.
    PRX Quantum 2 (2021). Published: 2021-06-14. arXiv: 2009.11790. doi: 10.1103/PRXQuantum.2.020340.
  14. Decoding across the quantum low-density parity-check code landscape.
    Joschka Roffe, David R. White, Simon Burton, Earl T. Campbell.
    Physical Review Research 2 (2020). Published: 2020-12-28. arXiv: 2005.07016. doi: 10.1103/PhysRevResearch.2.043423.
  15. Quantum Codes From Classical Graphical Models.
    Joschka Roffe, Stefan Zohren, Dominic Horsman, Nicholas Chancellor.
    IEEE Transactions on Information Theory 66, 130-146 (2020). Published: 2020-01-01. arXiv: 1804.07653. doi: 10.1109/TIT.2019.2938751.
  16. Quantum error correction: an introductory guide.
    Joschka Roffe.
    Contemporary Physics 60, 226-245 (2019). Published: 2019-07-03. arXiv: 1907.11157. doi: 10.1080/00107514.2019.1667078.
  17. The Coherent Parity Check Framework for Quantum Error Correction.
    Joschka Roffe.
    PhD Thesis, Durham University (2019). Published: 2019-04-29. doi: 10.5281/zenodo.7016827.
  18. Decoding quantum error correction with Ising model hardware.
    Joschka Roffe, Stefan Zohren, Dominic Horsman, Nicholas Chancellor.
    Preprint arXiv:1903.10254. Uploaded: 2019-03-25. arXiv: 1903.10254. doi: 10.48550/arXiv.1903.10254.
  19. Protecting quantum memories using coherent parity check codes.
    Joschka Roffe, David Headley, Nicholas Chancellor, Dominic Horsman, Viv Kendon.
    Quantum Science and Technology 3, 035010 (2018). Published: 2018-07-01. arXiv: 1709.01866. doi: 10.1088/2058-9565/aac64e.

About me

After leaving school, I spent a year working in the Analytical Technology group at Shell Research near Chester as part of the Year in Industry programme. Most of my time at Shell was spent operating electron microscopes for a range of clients, including - amongst others - the Ferarri Formula 1 team.

Following my year in industry I began a physics degree at the University of Manchester. This included a year abroad in sunnier climes at The University of California at Santa Barbara where I developed my interest in quantum technologies. On my return to Manchester I completed a Master's project studying open quantum systems under the supervision of Ahsan Nazir.

In 2015 I began a PhD in Quantum Computing at Durham University under the supervision of Viv Kendon, Dom Horsman and Nicholas Chancellor. My research focused on developing a new approach for the study of quantum error correction codes called the Coherent Parity Check (CPC) framework.

After my PhD I worked with Earl Campbell, Armanda Quintavalle, Yingkai Ouyang and David R White at Sheffield University as part of the Quantum Codes, Designs and Architectures project. Following this, I spent three years in Germany working in Jens Eisert's quantum computing group at the Free University Berlin.

I am now based at the University of Edinburgh where I work for the Quantum Software Lab.

Contact

Email: joschka@roffe.eu
Twitter: @quantumgizmos