Group members
  • Group Leader
  • Professor Gerald S. Buller

    Contact info:

    email: G.S.Buller[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 3069
    Fax: +44 (0)131 451 8083

    Prof Gerald S. Buller was born in Glasgow, Scotland in 1965. He graduated with BSc (Hons) Natural Philosophy from the University of Glasgow in 1986 and PhD in Physics from Heriot‑Watt University in 1989. In 1990, Prof Buller became a Lecturer in Physics at Heriot‑Watt University, was promoted to Reader in 2000 and made a Professor in 2006.

    Gerald Buller's research interests are mainly associated with photon‑counting technology and applications, including quantum communications, quantum-enhanced imaging, time‑of‑flight single‑photon ranging and imaging. He also has wider interests in semiconductor optoelectronic devices and optical thin film multilayer structures.

    Prof Buller was the founding Head of Heriot‑Watt's Institute of Photonics and Quantum Sciences (IPaQS) and led IPaQS from 2012 until 2015. In 2015, Professor Buller was awarded a prestigious EPSRC Established Career Fellowship in Quantum Technology. In 2020, Gerald became the Principal Investigator of the EPSRC Programme Grant "SPEXS" which investigates single‑photon detection in the short‑wave and mid‑wave infrared. The SPEXS project is a collaboration with the Universities of Glasgow, Edinburgh and Sheffield. In 2021, Gerald was appointed Principal Investigator of the Quantum Communications Hub funded through the UK National Quantum Technologies Programme.

    Gerald co‑founded TeraHertz Photonics Ltd. in 1998 and Helia Photonics Ltd. in 2002. He is currently Chairman of Helia Photonics Ltd.. He is a Fellow of the Optical Society of America, a Fellow of the Institute of Physics (UK), and a Fellow of the Royal Society of Edinburgh.

    Heriot‑Watt Research Portal
  • Associate Professors
  • Dr Ross J. Donaldson

    Contact info:

    email: R.Donaldson[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 8120

    Dr Ross Donaldson is from Perth, Scotland. He graduated with a BSc in Engineering Physics from Heriot‑Watt University in 2012. In 2016, he defended his Thesis titled: Quantum‑Security in Optical Fibre Networks, where he demonstrated experimental work in two quantum communication technologies; quantum digital signatures, and quantum state comparison amplification. Ross was then contracted as a post‑doctoral research associate (PDRA) to work on a quantum feed‑forward experiment and free‑space quantum receivers. Both his PhD and PDRA positions were at Heriot‑Watt University.

    Dr Donaldson is now an Associate Professor and Research Fellow funded by the Royal Academy of Engineering to explore practical optical ground receiver technology for satellite quantum communications. His broader research interests are primarily associated with quantum communication technologies and their roll‑out into practical service. This interest stems from his previous work on next‑generation quantum communications technologies.

    His research lab focuses on; quantum optical receivers for satellite QKD, practical implementation (1st gen service), high‑bandwidth (next‑gen service), and addressing background noise from natural (daytime) and artificial (jamming) in free space.

    He is a co‑investigator in the National Quantum Communications Hub, where he leads the Hub's Optical Ground Station (HOGS) design, development and operation for their in‑orbit demonstrator mission. Beyond the Hub, He has connections to other UK‑funded satellite QKD missions. In addition to scientific research, he has strong links to industry through five fully funded Innovate‑UK Industrial Strategy Challenge Fund projects, enabling knowledge transfer.

    General research interests:

    • Quantum optical receivers for satellite QKD,
    • Practical implementation (1st gen service),
    • High‑bandwidth (nex‑gen service),
    • Photonic devices for QKD,
    • Addressing implementation practical challenges.

    Dr Donaldson is a member of the Institute of Physics (IOP), SPIE, and Optica.

    Accepting MSc, PhD, and PDRA candidates. Also open to discussions with entrepreneurs looking to commercialise quantum technology

  • Assistant Professors
  • Dr Aurora Maccarone

    Contact info:

    email: a.maccarone[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 3056
    Fax: +44 (0)131 451 3136

    Dr Aurora Maccarone is from Palermo, Italy. She graduated with an MSc in Physics from the University of Palermo in 2011.

    After her undergraduate studies, she joined the Single‑Photon Group at Heriot‑Watt University as a doctoral student. Her research topic was to investigate single‑photon techniques for three dimensional imaging in highly scattering environments. During her PhD she conducted several experiments that led to the first demonstration of time correlated single‑photon counting for three dimensional underwater imaging. She received a PhD in Physics from Heriot‑Watt University in 2016 defending her thesis titled: Single‑photon detection techniques for underwater imaging.

    Following her doctoral studies, Aurora took her first position as a PDRA with the Single‑Photon Group and the Mostly Quantum Lab to investigate novel single‑photon detector technology for several applications, including free‑space/satellite‑based quantum communications and underwater imaging. On her second role as a PDRA, Aurora moved back to underwater imaging and worked on the first demonstration of three dimensional underwater imaging using single photon detector arrays.

    She is now a Research Fellow funded by the Royal Academy of Engineering and hosted at Heriot‑Watt University. During the Fellowship, Aurora will investigate state‑of‑the‑art single‑photon detector arrays for different underwater applications.

    Aurora's research interests include single‑photon technologies, imaging, and quantum communications. Aurora is currently a member of the International Society for Optics and Photonics (SPIE) and the Optical Society of America (OSA).

  • Managers
  • Mrs Fiona Neill

    Contact info:

    email: F.Neill[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Fiona was born in Glasgow and grew up in Lanark, South Lanarkshire. She studied computing at Motherwell College and then went on to study Electrical and Electronic Engineering at Bell College of Technology in Hamilton. Fiona moved to London in 1995 where she "fell" into a finance role at House of Fraser's head office.

    Fiona moved to Edinburgh in 2010 and started working at Heriot‑Watt University within the Engineering and Physical Sciences' finance office in 2015, joining the Single‑Photon Group as a Project Manager for SPEXS in July 2020.

    In her spare‑time she enjoys keeping fit and walking her dogs. Fiona is also a Les Mills Body Balance Instructor and a Les Mills Pilates Instructor as well as being a trained therapist in Reiki, Indian Head Massage and Hopi Ear Candling.

  • Research Fellows
  • Dr Aongus McCarthy

    Contact info:

    email: A.McCarthy[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 3056
    Fax: +44 (0)131 451 3136

    Aongus McCarthy is from Ferbane, Co. Offaly, Ireland. He graduated with a BSc from University College Galway in 1989, a Diploma in Electronic Engineering from the Institute of Technology in Carlow, Ireland in 1990 and received a BSc in Physical Optoelectronics from Essex University, England in 1991. Between 1991 and starting his PhD at Heriot‑Watt University in 1997, he spent two years as an Associate on a Department of Trade and Industry (DTI) run Teaching Company Scheme (now known as Knowledge Transfer Partnerships) between Coventry University and Signam Limited in Warwick. He was then employed by Signam and was the leader of the R & D Design Team that developed a pre‑production prototype of a thermal transfer printer for printing onto non‑absorbent polyester type materials.

    He received a PhD degree in Physics from Heriot‑Watt University in 2002. His work focussed on the development of a polymer based integration platform for a high‑speed optoelectronic crosspoint switch demonstrator which incorporated direct laser written multimode waveguides and mirror surfaces. Since becoming a Research Associate, Aongus has designed, assembled and tested an optical routing module for a multiple‑wavelength time‑of‑flight sensor based on time‑correlated single photon counting, developed a polymer‑based, multi‑layer planar lightwave circuit platform, and is currently working on the optical and optomechanical design of a multi‑parameter fluorescence lifetime imaging microscope.

    His research interests include optical interconnects (free‑space and guided‑wave), optical and optomechanical design, direct laser writing techniques and microscope systems. Aongus has been a member of the Optical Society of America (OSA) since 1999 and a member of the Institute of Electrical and Electronics Engineers (IEEE) Photonics Society (IPS) since 2002.

    Heriot‑Watt Research Portal
  • Dr Rachael Tobin

    Rachael was born in Edinburgh, Scotland and grew up in Danderhall, Midlothian.

    She moved to Arizona, USA and earned an Associate of Arts degree in Japanese Language in 2010. Following this, she undertook a BSc (Hons) in Physics at Heriot‑Watt University, graduating in June 2015.

    In 2015, she joined the Single‑Photon Group at Heriot‑Watt University working on time‑of‑flight depth measurements in extreme environments under the supervision of Prof Gerald S. Buller. Rachael earned her PhD in 2019 and continued her research as a Postdoctoral Researcher.

    Rachael is currently a Research Fellow funded by the Royal Academy of Engineering where she is investigating the potential for state-of-the-art single-photon detectors for rapid, high-resolution remote sensing at long-range and in extreme conditions.

    In her free time Rachael enjoys playing flute, gaming, reading, running and cooking.

  • Dr Xin Yi

    Contact info:

    email: xin.yi[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC
    Fax: TBC

    Xin Yi was born in Chongqing, China in 1991. He received his Bachelor degree in Electronic and Electrical Engineering at The University of Sheffield in 2015. He obtained his PhD at the same university working on Antimony based avalanche photodiodes (APDs) 2020. This work demonstrated some of the lowest excess noise in linear mode Antimony based APDs.

    In 2020, he moved to Edinburgh and joined the Single‑Photon Group at Heriot‑Watt University as a Postdoctoral Researcher, working on the design and optoelectronic chararterisation of Ge‑on‑Si single photon avalanche detectors. He is now a Research Fellow funded by EPSRC and hosted at Heriot-Watt University. During the Fellowship, he will investigate state of the art single‑photon detectors based on Antimony based alloys for room temperature near short-wave infrared applications. Xin Yi is a member of IEEE and SPIE. He is currently accepting PhD candidates and open to discussing research collaborations.

    In his spare time Xin Yi enjoys sports, reading and travelling.

  • Research Associates
  • Dr Harikumar K. Chandrasekharan

    Hari received a B.Sc. degree in Physics from Calicut University in 2008 and an M.Sc. degree in Photonics and Biophonics from Madras University in 2011. He finished his PhD at Heriot-Watt University, in the Photonics Instrumentation Group under the guidance of Prof Robert Thomson. His doctoral dissertation entitled "Time-resolved imaging of guided wave phenomena", mainly focused on the use of novel imaging technologies for time-resolved photonic applications. This work investigated the potential application of a novel single-photon sensitive camera for a variety of applications that involves time-stretch photonic imaging, time-resolved discrete optics in photonic lattices, and speciality fibre optics.

    After completing Research associate roles in various research groups at HWU, he joined the Single‑Photon Group as a post-doctoral researcher, currently working on implementing efficient optical detection protocols for satellite quantum communication under the supervision of Dr. Ross Donaldson.

  • Dr Pete Connolly

    Contact info:

    email: pc23[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC
    Fax: TBC

    Pete Connolly grew up in Staffordshire, England, before studying for a degree in Advertising at the University of Northampton, earning a BA (Hons) in 2008. After working in advertising, Peter returned to education and graduated with an MSc (Hons) in Physics from the University of Birmingham in 2016.

    In October 2016 he joined the Single‑Photon Group at Heriot‑Watt University working on next generation imaging using sparse single‑photon data under the supervision of Prof. Gerald S. Buller. Pete earned his Doctorate in July 2020 and continued working as a Postdoctoral Researcher with the Single‑Photon Group on the topic of enhanced quantum imaging.

    In his spare time Pete plays football, practices taekwondo and enjoys travelling.

  • Dr Elizabeth Eso

    Contact info:

    email: e.eso[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Elizabeth Eso received her B.Eng (Hons.) in Electrical and Electronics Engineering from the Abubakar Tafawa Balewa University, Nigeria (2011) and MSc in Microelectronics and Communications Engineering from the Northumbria University Newcastle, UK (2014) with Distinction and also carried out her PhD research degree in the same University. Earlier on, in 2004 she won the Best Female Position in Mathematics in Nigeria, awarded by the Mathematical Association of Nigeria.

    Elizabeth Eso was a Marie Curie Early Stage Researcher at the Northumbria University Newcastle before she joined the Single‑Photon Group at Heriot‑Watt University in September 2021 as a Research Associate.

    Elizabeth's research interests include free‑space optics, quantum key distribution, visible light communications and optical camera communications. She is a member of the Institute of Electrical and Electronics Engineers (IEEE) and the Institution of Engineering and Technology (IET).

  • Dr Fiona Fleming

    Contact info:

    email: f.fleming[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 4687
    Fax: +44 (0)131 451 3136

    Fiona E. Fleming was born in Melrose in the Scottish Borders in 1991. She grew up in Berwickshire on the South‑east coast of Scotland.

    She completed her undergraduate degree at Heriot‑Watt University, graduating in 2015 with an MPhys(Hons). In October 2015 she began her PhD in the Nonlinear Optics Group at Heriot‑Watt University working on the development of compact high repetition rate mid‑IR solid‑state lasers.

    On completion of her PhD in October 2019 Fiona joined the Single‑Photon Group at Heriot‑Watt University as a Postdoctoral Researcher working on infrared single‑photon counting using integrated Ge‑on‑Si SPADs (single‑photon avalanche detectors). In April 2022 she also began work on a collaboration with the Jet Propulsion Laboratory and Caltech in Pasadena, California which is centred on developing the newest generation of SNSPD arrays for long range single-photon LIDAR enabled by the unprecedented temporal and spatial resolution offered by the JPL SNSPD arrays.

    In her spare time Fiona enjoys hiking, watching football and tennis, reading and baking.

  • Dr Yoann Noblet

    Contact info:

    email: y.noblet[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Yoann was born in Caen, France in 1986 and grew up in Cabourg, Normandy.

    He graduated with a Higher National Diploma in Photonics from the University of Rennes in 2006. He then moved to Glasgow and graduated with an MSc in Photonics from the University of Strathclyde in 2010. He then decided to start a joint PhD between the University of Strathclyde and Macquarie University (Australia) working on Frequency Modified Feedback in External Cavity Semiconductor Laser Systems.

    After completion of his PhD, Yoann started working in industry, focusing on thin-film coatings and automation. In 2018 he came back to the University of Strathclyde as a Research Associate working on the development of a novel and compact multispectral imaging instrument for satellite deployment. In 2021 Yoann joined the Single‑Photon Group at Heriot‑Watt University as a Research Associate to work on free space quantum communications.

    In his free time Yoann enjoys playing basketball, skiing, hiking, boardgames and gaming.

  • Dr Rui Zhang

    Contact info:

    email: r.zhang[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Rui is from Guangdong, China He participated in a 2+2 exchange program and was awarded dual degrees in 2018: a BSc in Optoelectronic Information Science and Engineering from South China University of Technology, and a BEng in Electronic Engineering from the University of Edinburgh. Building on his academic success, Rui went on to obtain his PhD degree from the University of Edinburgh in 2023. His research was centred on time‑resolved applications using CMOS SPAD.

    In his research journey, Rui pioneered the use of a LiDAR system based on time‑of‑flight to profile water surface waves in a laboratory wave tank setting. He also significantly contributed to the development of fluorescence lifetime imaging techniques by integrating a CMOS SPAD line sensor for advanced retinal imaging applications. Today, he works as a Postdoctoral Research Associate with the Single-Photon Group, where he delves into the realms of underwater single‑photon LiDAR measurements.

    Outside of his professional life, Rui takes pleasure in badminton, photography, reading, and travelling.

  • Dr Lisa Saalbach

    Contact info:

    email: l.saalbach[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 449 3648

    Lisa moved to Edinburgh in 2011 to study Chemical Physics at Heriot‑Watt University, obtaining her MPhys in 2016. Following this she started a PhD in the Ultrafast Molecular Dynamics Group at Heriot‑Watt University, which focused on time‑resolved imaging studies of the ultrafast relaxation dynamics in molecular systems.

    In February 2020, Lisa joined the Single‑Photon Group at Heriot‑Watt as a Research Associate. She works on the characterisation of novel Ge-on-Si single-photon avalanche diode detectors.

    In her spare time, Lisa enjoys spending time with friends and hiking

  • Dr Ewan C. Wade

    Contact info:

    email: ecw3[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 4687
    Fax: +44 (0)131 451 3136

    Ewan C. Wade was born in Glasgow, Scotland in 1996. He graduated from the University of Strathclyde in 2019 with an MPhys degree with a specialisation in Photonics. During his last two years at Strathclyde, Ewan worked on Neuromorphic Photonics projects and was fortunate enough to have the work from his 4th‑year project published during the latter half of his final year.

    Ewan is currently working towards a PhD under the supervision of Prof. Gerald S. Buller with the support of a sponsorship from the Defence Science and Technology Laboratory. Ewan joined the Single‑Photon Group in 2019 and his work will be focussed on time‑of‑flight ranging and imaging.

    In his spare time, Ewan enjoys playing the piano, listening to music, gaming and movies.

  • Postgraduate Students
  • Ms Harmony Li

    Contact info:

    email: zl2094[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Harmony was born in Guangdong, China in 2000. She moved to England in 2016 and attended Bloxham School in Oxfordshire.

    She graduated from the University of St Andrews in 2023 and received an MPhys in Theoretical Physics and Mathematics. Throughout her undergraduate years, Harmony cultivated a profound passion for quantum technology and its applications.

    In October the same year, she joined the Single‑Photon Group at Heriot‑Watt University, under the supervision of Prof Gerald S. Buller.

    During her spare time, Harmony enjoys going to the gym, cooking, cycling and exploring nature.

  • Ms Mrudul Modak

    Contact info:

    email: mam2016[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC
    Fax: +44 (0)131 451 3136

    Mrudul was born in Pune, India. She completed her masters from Pune University in 2020 and worked at the University for two years as a project associate.

    Mrudul is currently working towards a PhD under the supervision of Prof Gerald S. Buller. She joined the Single‑Photon Group in 2023.

    In her spare time, Mrudul enjoys spending time with her friends or with a book and a hot cup of tea.

  • Mr Dave Muir

    Contact info:

    email: dm140[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 4687
    Fax: +44 (0)131 451 3136

    Dave Muir was born in Edinburgh. In 2002 he completed a Bcomm in Business Studies before going on to do a Masters in Chinese. After studying he went on to work in Financial Services for 15 years which started in Jersey and ended working as a Quantitative Analyst in Edinburgh. When he became jaded with the world of finance he returned to university to do a Bsc in Mathematical Physics.

    Following his graduation in June 2022 he joined the Single‑Photon Group at Heriot‑Watt University, working on SPADS under the supervision of Prof Gerald S. Buller.

    In his spare time Dave enjoys playing with his cats, gardening and cooking.

  • Mr Cameron Simmons

    Contact info:

    email: ccs2000[anti-spam](at)[remove]hw.ac.uk
    Telephone: TBC

    Cameron was born in 1999 and grew up in Lincolnshire. He graduated in 2021 with an MEng in Engineering Science from St. Anne's College, Oxford, specialising in optoelectronics and communications. While there he interned at Archangel Lightworks and undertook a 4th year project in short‑range free‑space visible light communications.

    In 2021 Cameron joined the Single‑Photon Group at Heriot‑Watt University to complete a PhD in free‑space Quantum Communications under the supervision of Dr. Ross Donaldson.

    Outside of the university Cameron is an avid runner and cyclist as well as a player of guitar and double bass.

  • Mr Arran Sykes

    Contact info:

    email: as321[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 4687
    Fax: +44 (0)131 451 3136

    Arran Sykes was born in 1996 and grew up in Falkirk. He studied for 2 years at college to obtain an HND in Electrical Engineering at Forth Valley College with aims of working with Scottish Power. He then changed path slightly and moved on to do a BSc in Mathematical Physics at Heriot-Watt University from which he graduated in 2022.

    Shortly after graduating he joined the Single‑Photon Group at Heriot‑Watt University, working on Quantum Enhanced Imaging in Extreme Environments under the supervision of Prof Gerald S. Buller.

    During his free time Arran likes to spend time with his dog and also enjoys reading and gaming.

  • Mr Albert de Dios Carbajal

    Contact info:

    email: ad2010[anti-spam](at)[remove]hw.ac.uk
    Telephone: +44 (0)131 451 4687
    Fax: +44 (0)131 451 3136

    Albert was born in 2002 and grew up in Barcelona. He moved to Edinburgh in 2020 to pursue a degree in Physics at Heriot-Watt University. As part of his undergraduate programme, he worked under the supervision of Dr Aurora Maccarone in his final year project investigating underwater single-photon imaging for target discrimination in cluttered scenarios.

    He graduated with a BSc in Physics from Heriot‑Watt University in 2024. In September of that same year he joined the Single‑Photon Group working on novel single-photon techniques for underwater imaging under the supervision of Dr Aurora Maccarone.

    In his spare time, Albert enjoys cooking, playing tennis, reading and writing.