About Us

People

Learn more about our current team, including our academic staff and post-doctoral and PhD researchers.

Academic Staff 

Professor Polina Bayvel - Head of the Optical Networks Group / Prof. of Optical Communications

BSc(Eng), PhD, CBE, FRS, FREng, FIEEE, FOSA, FInstP, HonFIET

Professor Polina Bayvel is the Head of the Optical Networks Group at UCL which she also set up in 1994. Her research interests are in the area of optical communications and include wavelength-routed optical networks, high-speed optical transmission, and the study and mitigation of fibre nonlinearities. She was one of the first to show the feasibility of using the wavelength domain for routing in optical networks, and designed wavelength-selective devices needed for their characterisation and implementation. More recently she has focused on the study of capacity limits in nonlinear optical networks and optical networks for the cloud. She has authored or co-authored more than 350 refereed journal and conference papers.

Polina Bayvel received her BSc (Eng) and PhD degrees in Electronic & Electrical Engineering from University of London, UK, in 1986 and 1990, respectively. In 1990, she was with the Fiber Optics Laboratory, General Physics Institute, Moscow (formerly USSR, now Russian Academy of Sciences), under the Royal Society Postdoctoral Exchange Fellowship. She was a Principal Systems Engineer with STC Submarine Systems Ltd, London, UK, and Nortel Networks (Harlow, UK, and Ottawa, ON, Canada), where she was involved in the design and planning of optical fibre transmission networks. During 1994-2004, she held a Royal Society University Research Fellowship at University College London (UCL), and in 2002, she was appointed to a Chair in Optical Communications and Networks.

Professor Bayvel is a Fellow of the Royal Society (FRS), Royal Academy of Engineering (FREng), Optical Society of America (FOSA), Institute of Electronic & Electrical Engineers (FIEEE), the UK Institute of Physics (IoP), and the Institute of Engineering and Technology (IET). She was the recipient of the Royal Society Wolfson Research Merit Award (2007-2012), the 2013 IEEE Photonics Society Engineering Achievement Award, the 2014 Royal Society Clifford Patterson Prize Lecture and Medal, and in 2015 together with five members of her group, she received the Royal Academy of Engineering Colin Campbell Mitchell Award for 'pioneering contributions to optical communications technology'.

She was the PI of the UK EPSRC Programme Grant UNLOC (2012-2018), focused on unlocking - and maximising - the capacity of optical communications, and now leads the TRANSNET Programme Grant (2018-2024).

She was awarded CBE (Commander of the Order of the British Empire) in the 2017 New Year's Honours List for services to engineering.  

Dr Kari Aaron Clark - Royal Academy of Engineering Senior Research Fellow

Dr Kari A. Clark received a BSc MPhys degree in Physics at the University of Warwick in 2013. He then completed two internships in the electronic engineering industry and joined the Optical Networks Group at UCL in 2014. In 2016, he completed a further nine-month internship at Microsoft Research Cambridge, applying his research in an industrial context. In 2021, he was awarded the PhD and became a Research Fellow with the TRANSNET Programme within the Optical Networks Group.

Dr Clark is currently a Royal Academy of Engineering Senior Research Fellow with the Optical Networks Group (ONG) UCL, having been awarded a 5-year Research Fellowship with the Royal Academy of Engineering in 2022. His fellowship research is to explore methods of optical clock synchronisation to achieve sub-nanosecond clock synchronisation accuracy in 6G radio access networks. Further information about Dr Clark’s fellowship can be found here. His doctoral research focussed on using central optical clock synchronization and clock phase caching to achieve sub-nanosecond clock and data recovery times in optically switched data centre networks.

His research interests include:

• Optical clock distribution
• Optical fibre time-of-flight compensation
• Time synchronised radio access networks
• Synchronised data centre communications
• Clock phase caching
• Sub-nanosecond clock and data recovery

Awards and Funding:

• Royal Academy of Engineering Research Fellowship (2022 to 2027)
• Overall Winner of the EPSRC Connection Nation Pioneers Competition 2018
• Bronze in Engineering at the STEM for BRITAIN 2019 competition held at UK parliament

Contact email: kari.clark.14@ucl.ac.uk

Dr Filipe M. Ferreira - UKRI Future Leaders Fellow

Filipe M. Ferreira received a PhD in Electrical and Computer Engineering from the University of Coimbra, Portugal, in 2014 for his work on high capacity optical transmission systems based on mode division multiplexing.

During this time, he worked as a Research Engineer for the optical networks Research & Technology division of Coriant (former Nokia Siemens Networks), leading activities on the EU-FP7 research project MODEGAP, including: few-mode fibres nonlinear modelling and profile design, advanced optical links design and simulation. 

In 2015 he was awarded a Marie Curie Individual Fellowship to carry out research on space division multiplexing. During this fellowship, he investigated the linear and nonlinear coupling mechanisms in fibres for spatial division multiplexing, and the opportunities for digital back-propagation.

Filipe joined the Optical Networks Group at UCL as a Senior Research Fellow in October 2019 to work on the EPSRC TRANSNET project, working on the development of intelligent transceivers aimed at better approaching the nonlinear Shannon limit in typical optical fibre networks.

In October 2020 Filipe was awarded a UKRI Future Leaders Fellowship to develop new technologies capable of establishing thousands of parallel optical paths over a single optical fibre strand which will dramatically expand the capacity of the Internet. The project aims to produce a new photonic processor that merges photonic integrated circuits and machine learning so that large-scale spatial parallelism can be achieved within every optical fibre.

Contact email: f.ferreira@ucl.ac.uk

Professor Robert Killey - Professor in Optical Communications

Robert Killey received his BEng degree in Electronic and Communications Engineering from the University of Bristol in 1992 and an MSc in Microwaves and Optoelectronics from UCL in 1994. He received a DPhil degree from the University of Oxford in 1998. His doctoral work was on InGaAsP Fabry–Perot optical modulators and their applications in soliton communications.

He has been a member of the academic staff at UCL since 2000 and is currently a co-investigator on the EPSRC TRANSNET project; a multidisciplinary research programme investigating intelligent resource allocation in dynamic optical networks

Professor Killey is an Associate Editor of the IEEE/OSA Journal of Lightwave Technology and the IEEE Photonics journal, and has served on the Technical Programme Committees of OFC and ECOC. He was a recipient of the 2015 Royal Academy of Engineering 2015 Colin Campbell Award and is a Senior Member of the IEEE.

Current research interests:

• Modelling and experimental investigations of the effects of fibre nonlinearity on high bit-rate WDM data transmission
• Simplified direct detection and coherent optical transceivers
• The applications of digital signal processing for transmission impairment mitigation in high capacity optical communication systems

Contact email: rkilley@ee.ucl.ac.uk 

Dr Zhixin Liu - Associate Professor in Optical Communications and Networks

Zhixin Liu received his PhD degree in Information Engineering from the Chinese University of Hong Kong, in 2012. After a short start-up experience, he joined the Optoelectronics Research Centre (ORC) at the University of Southampton in 2013 and became a Senior Research Fellow in 2015. In 2016, he joined the optical networks group at the Department of Electronics and Electrical Engineering at UCL and became an Associate Professor in 2021. Dr Liu is a senior member of both IEEE and Optica (formerly OSA).

His research areas are optical signal processing and its applications in communication systems and scientific equipment. He has pioneered new techniques for high precision data conversion and low-latency data communications that have led to several world-first demonstrations. Dr Liu has co-authored more than 100 papers in international peer-reviewed journals and conferences, with several high-profile papers in Nature Electronics, Nature Communications, eight invited papers to the IEEE/OSA Journal of Lightwave Technology as well as top-ranked publications in leading optical communication conferences (OFC and ECOC), including seven post-deadline papers.

Dr Liu is regularly invited to speak at leading international conferences and serves on the technical programme committees of CLEO-PR, OECC and ACP. He also holds two patents, with one licenced to a leading industrial manufacturer. Dr Liu has been a PI on more than ten grants from Industry and Research Councils, totalling over £1.7M. He is also a co-investigator on the £6.1m EPSRC Programme grant TRANSNET.

Contact email: zhixin.liu@ucl.ac.uk

His research interests include: 

• High-performance frequency comb
• Coherent signal processing
• Low-latency, low-power consumption transceivers for data centre interconnects
• Integrated photonic circuits for communication systems 

Current projects:

• Accurate Time and radio signal distribution through Optical access networks to enable sub-Metre positioning accuracy (ATOM)
• Overcoming Resolution and Bandwidth limIT in radio-frequency Signal digitisation (ORBITS)
• Advanced Signal Generation And Detection System For Next-generation
• PhotoDAC: Photonically-synthesized Digital-to-Analogue Conversion
• TRANSNET : Transforming networks - building an intelligent optical infrastructure  

Past projects:

• Development of a pre-commercialisation frequency comb prototype for cloud data centre networks and metro telecom systems
• Photonic-assisted Real-time Oscilloscope
• Optically-switched Data Centre Networks Using Thermal-insensitive Hollow-Core Fibre
• Optically-assisted Fourier analysis
• UNLOC: UNLocking the Capacity of Optical Communications

Dr Alfonso Ruocco - Lecturer in Optical Communications and Networks

Alfonso Ruocco is currently a Lecturer in Optical Communications and Networks in the Department of Electrical Engineering at the University College London. He received his MEng in Electronic Engineering from the Federico II University of Naples in 2011 and his PhD in Photonics Engineering from the University of Ghent/IMEC in 2016, where he explored novel high complexity integrated photonic circuits.

He was subsequently appointed as a Postdoctoral Associate within the Research Laboratory of Electronics at the Massachusetts Institute of Technology, where he investigated novel CMOS-compatible integrated photonics systems for metrology and communication systems. Following this, Alfonso held the position of Research Associate and Senior Research Associate within the Electrical Engineering Department at the University of Cambridge, where he investigated novel hybrid nanomaterials/CMOS-compatible photonic platforms for communication systems and ultrafast photonics.

Alfonso’s current research interests include integrated photonic systems implemented on high index contrast platforms, photonic transceivers, ultrafast and quantum photonics.

Contact email: a.ruocco@ucl.ac.uk

Dr Eric Sillekens - Royal Academy of Engineering Senior Research Fellow

Eric Sillekens is a Senior Research Fellow, supported by a Royal Academy of Engineering (RAEng) Research Fellowship. He currently leads the EPIC DSP project, advancing low-complexity digital signal processing (DSP) and energy-efficient semiconductor optical amplifiers (SOAs) to reduce power consumption in long-haul fibre transmission systems through innovations in coded modulation and machine learning.

Eric completed his BSc and MSc in Electrical Engineering at the Eindhoven University of Technology in 2012 and 2015, respectively, before earning his PhD at University College London (UCL) in 2020, where he focused on advanced coded modulation for optical fibre communication. Previously, he contributed to the TRANSNET Programme at UCL, designing modulation formats that balance fibre nonlinearity and shaping gain. His ongoing research aims to push the limits of capacity and energy efficiency in next-generation optical communication systems.

Contact email: e.sillekens@ucl.ac.uk

Professor Georgios Zervas - Professor of Optical Networked Systems, EPSRC Fellow

George Zervas is currently Professor of Optical Networked Systems in the Department of Electrical and Electronic Engineering at University College London. He received his MEng degree in Electronic and Telecommunication Systems Engineering with distinction and PhD degree in optical networks from the University of Essex in 2003 and 2009 respectively. Following this, George held the positions of Research Associate and subsequently Research Fellow and Lecturer as a member of the High-Performance Networks Group at the University of Essex where he investigated multi-granular optical switching. 

Between 2012-16 he was appointed Lecturer and Senior Lecturer at the University of Bristol where he led the research activities on optical networked systems with an emphasis on optical switching, flexible and space division multiplexed networking, programmable electronic and optical hardware as well as data centre systems. He also held the position of Visiting Associate Professor at Keio University, Tokyo. He is the recipient of the prestigious 5-year Fellowship from the Engineering and Physical Sciences Research Council (EPSRC) within Information and Communications Technology in the U.K. 

He is the author and co-author of over 275 international peer-reviewed journal and conference papers including numerous prestigious post-deadline papers at ECOC/OFC as well as best paper awards. He has also given over 40 invited talks at several international conferences. His research interests lie in the fields of optical networked systems for data centres, high-performance computing and telecoms with a particular focus on optical switched interconnects, topologies, control, architectures and compute and network co-design. 

George has been involved in several current and past EC and EPSRC and industrial funded projects as principal and co-investigator. He has been a Technical Programme Committee member on international conferences such as OFC, ICC, Globecom, ONDM and ACP. He is an associate editor of IEEE Networking Letters and has been serving as guest associate editor on IEEE JOCN. Dr Zervas has been involved in the Internet Engineering Task Force (IETF) and Open Grid Forum (OGF) standardisation fora. George is also a member of the EPSRC Peer Review Associate College and has served as an expert reviewer in other non-UK national funding bodies.

George is currently an EPSRC Fellow (OptoCloud) and co-investigator on the TRANSNET programme grant. His research has been funded and supported by industry partners including Microsoft, Huber+Suhner Polatis, British Telecom, Sumitomo Electric, II-VI, Xilinx and Micron.

For more information please visit my personal website. 

Contact email: g.zervas@ucl.ac.uk 

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General Enquiries 

We are always happy to hear from post-doctoral researchers and PhD students interested in working with us. We are looking for team members with aptitude and interest in hands-on experimental work in the areas of high-speed optical fibre transmission systems, digital signal processing and machine learning for optical communications. Applicants should have an excellent academic record with a first degree in electronic and electrical engineering, physics or a related discipline and demonstrate enthusiasm and ability for research work. 

Please contact Professor Polina Bayvel in the first instance: p.bayvel@ucl.ac.uk

Alumni

Many outstanding students and research fellows have passed through the Optical Networks Group (and come back again!) since it was founded in 1994. The training we provide our students has enabled them to have very successful careers at a number of leading companies in the field.

Most of our alumni are listed below, but if you were a member of our group and your name and contact details are not on the list, please get in touch with Professor Polina Bayvel and let us know where you are now. 

Alumni Testimonials

If you are a former ONG member, we would love to hear from you!

Our alumni are the heart of our vibrant community. We would love to spotlight your achievements to not only inspire but to show the impact that our growing community have had across the world.

All you need to do is complete a short form, which you can access here. 

For further information on the form, please contact Professor Polina Bayvel.