Optical Theory Group

3 Apr 2025: We are looking forward to the Focus on Microscopy conference. This year Matthew and Ganesh will be in Taipei, Taiwan. In addition to his oral talk, Matthew will present a poster on some of the recent IDMxS work on nanoparticle imaging based assays. If you want a preview of the poster you can view it here.

18 Mar 2025: Matthew and Ganesh will both be presenting oral talks at Focus on Microscopy 2025. We are looking forward to an interesting conference and hope to see some of you there.

18 Mar 2025: Check out our latest preprint on arXiv. In this work we introduce an approach to design high order EPs using transformation optics principles. Our approach helps alleviating many of the limitations of traditional Hamiltonian based approaches, offering new pathways for developing topological optical devices with enhanced functionality.

17 Mar 2025: We are excited to share our new GitHub repository, offering open-source tools for researchers to analyze and understand light propagation in complex optical networks. This resource provides the means calculating scattering matrices, study resonant properties and much more. Explore the latest code here.

19 Feb 2025: We are pleased to announce our paper, Generalized Wigner-Smith analysis of resonance perturbations in arbitrary Q non-Hermitian systems, has been accepted for publication in Physical Review Research! This research builds on our earlier work, bridging the Wigner-Smith formalism with electromagnetic perturbation theory for open resonant systems, regardless of quality factor. We have demonstrated its utility through practical examples, including nanoresonator sensor design and uncovering enhanced sensitivity in scattering zeros. This advancement opens new avenues for understanding and manipulating resonances in non-Hermitian systems.

8 Jan 2025: OTG is happy to welcome a new PhD student to our ranks - Baruva TS. He obtained his integrated Bachelors and Masters from the Department of Physics, IISER Mohali. His project will focus on sensing properties of complex photonic and plasmonic networks.

28 Dec 2024: Ganesh will be presenting some of our computational imaging work at the upcoming International Conference on Emerging Trends in Optical Technology running from 2 Jan to 4 Jan 2025. The conference is hosted by SRM University–AP, Andhra Pradesh, India. If you are there, then please come say "Hi" - we would love to meet you.

28 Nov 2024: We are happy to announce that we have just been awarded a small Ministry of Education Tier 1 grant to investigate coherence effects in lensless imaging. We will apply what we learn to deploy these powerful tools in our continuing guest for highly sensitive digital diagnostic assays.

10 Nov 2024: Niall presented some of his latest work on perturbing random networks at the IEEE Photonics Conference (IPC), 2024 in Rome, Italy. You can see the abstract here. If you happened to see the talk or would like to know more then get in touch and we are happy to discuss any possiblilites for collaborations.

28 Oct 2024: OTG welcomes its latest addition - Tanmay Bhowmik. He joins our efforts at IDMxS and will deploy his expertise in simulating plasmonic and nanophotonic devices to help us design improved molecular analytic platforms and nanoparticle assays.

28 Oct 2024: We're pleased to share our most recent work on Generalized Wigner-Smith analysis of resonance perturbations in low Q non-Hermitian systems which has just gone live on arXiv. This is a follow on work from our earlier generalised Wigner Smith operator based perturbation theory article and presents a number of key generalisations to broaden the applicability and validity of our theory.

22 Aug 2024: We just posted some exciting new results from the Optical Theory Group to arXiv. Specifically, we demonstrate a novel perturbation theory based on generalised Wigner-Smith operators. This provides a powerful tool for describing resonance shifts and broadening in open non-Hermitian systems. We also have another work in the pipeline to expand the domain of validy of the presented theory, so watch this space for more updates.

9 Aug 2024: Matthew has just got back from CLEO Pacific Rim, held in Incheon, South Korea. He was honoured to be asked to give a tutorial talk on digital molecular analytics at the conference, where he also presented on our latest random matrix theory results. Whilst in South Korea, Matthew also attended the NTU-Yonsei Workshop on Photonics and Quantum Applications. It was great to meet many new colleagues from around Asia and beyond and even to catch up with a few surprise old friends as well.

1 Aug 2024: The start of term has quickly come back around and this semester brings a new IGP PhD student, Sulagna Dutta, to the group to whom we extend a very warm welcome. Sulagna got her BSc from St Xaviers College, Kolkata and holds a MSc and MTech from Calcutta University and IIT Delhi respectively. Her project will focus on various aspects of polarised light in scattering media and how it can be leveraged for imaging.

1 Jul 2024: We extend a very warm welcome to our latest member Ganesh Balasubramaniam! Ganesh has a host of expertise in computational imaging techniques and we look forward to his contributions to our efforts in developing robust low cost imaging based diagnostic assays.

21 Jun 2024: We are very happy to report that our latest work on a dual pool bootstrapping approach has just been acceptedfor publication in Physical Review E. You can read the preprint on arXiv or here. It was great to work with Gary Greaves from SPMS, NTU, on some of the mathematics for this article. I look forward to future collaborations with him in the future.

14 Jun 2024: This week Matthew was at the 3rd Joensuu Conference on Coherence and Random Polarization held in Finland, presenting our polarised random matrix theory work. There were lots of interesting presentations, stimulating discussions and plenty of other activities on the schedule. It was great to catch up with some familiar faces and we look forward to attending the next one in the series.

13 May 2024: Looking for a PhD in theoretical optics, information theory or biosensing? Why not consider joining the Optical Theory Group in EEE at Nanyang Technological University in Singapore? We have a scholarship available for the January 2025 intake! The application deadline is 31st July 2024. Further details can be found here. Some available projects are listed here, but we are always open to discuss possible research with you to ensure the best fit. Please contact Matthew Foreman for further information.

7 May 2024: Today we were at the ICCAS-IDMxS Joint Workshop. Thanks to everyone who joined us. There was an interesting and diverse range of talks and some stimulating discussions to follow. I look forward to the next one.

7 May 2024: We have uploaded some of our latest work to arXiv. This work reports on a dual-pool based bootstrapping approach to improve computation times when using cascaded random matrix models. We investigate the statistical biases and correlations that can be introduced through use of such a technique and show that in practical domains these are fortunately of little practical concern.

22 Apr 2024: OTG is thrilled to welcome another new group member, Kiran Mujeeb. Kiran brings a wealth of expertise on optical and plasmonic surface waves and will be a valuable asset to the team, looking at novel surface waves for single particle sensing applications.

3 Apr 2024: Matthew will be presenting at CLEO Pacific Rim 2024 and giving an invited tutorial talk. If you are going then please come and say hello!

11 Mar 2024: We are excited to announce Radhika Nair as its newest Research Fellow. Radhika brings a strong background in SERS-based sensing, 2D materials, and plasmonic nanoparticles, all of which will be instrumental to the team's ongoing research endeavors at IDMxS.

3 Feb 2024: Matthew has been invited to present some of the group's work at the 3rd Joensuu Conference on Coherence and Random Polarization to be held in June in Finland. He is looking forward to what is sure to be an interesting set of talks, catching up with old friends and hopefully meeting some new ones there too.

15 Jan 2024: It is wonderful to be able to welcome our latest group member, Jennifer Tanadi, who is joining as a PhD candidate. Jennifer graduated with her BEng from the National University of Singapore and has since been working at the Institute of High-Performance Computing (A*STAR) simulating nanostructures and silicon photonic devices. Her project will consider modelling of nanoplasmonic and photonic systems for sensing applications within the fold of IDMxS.

14 Jan 2024: We have a new opening for a Research Fellow at the Insitute for Digital Molecular Analytics and Science (IDMxS). The position will focus on analysing nanoparticles and biomolecules through polarisation engineering (see here for details and to apply). Applications should be made via the NTU Workday portal. Feel free to get in touch if you have questions.

5 Jan 2024: Today we held the 2nd IDMxS symposium at NTU. Attended by many of the regular IDMxS faces, but also by many invited speakers and new and incoming members, it was a great chance to jointly discuss how the institute is moving forward towards its goals of developing cheap, robust and sensitive diagnostic tools and see some of the interdisciplinary work being done.

1 Dec 2023: The winter conference season is in full swing and as part of this both Niall and Matthew gave oral presentations of their work at the International Conference on Optical and Photonic Engineering, held locally here in Singapore. It was nice to meet many new faces and we hope to be able to talk further and collaborate with those we meet in the future.

22 Nov 2023: Matthew just got back from attending the International Symposium on Imaging, Sensing and Optical Memory (ISOM23). An interesting range of talks in a beautiful location. Matthew presented some of our work on surface plasmon based particle detection. It was great to meet some old friends and make some new ones.

17 Nov 2023: We are happy to announce that we have just been awarded a small Ministry of Education seed grant to investigate some novel resonances in anisotropic optical resonators. We will be recruiting for this project, so watch this space for upcoming job alerts or check our vacancy listing.

1 Oct 2023: After 6 years Matthew's term as Associate Editor at Optics Express is sadly coming to a close. It has been a highly rewarding journey and very interesting to see the other side of the publishing process. Thank you to all the staff at OpEx for their help and support over the years. Although the OpEx tenure is over, it actually marks the beginning of a new exciting chapter, with Matthew staying within the Optica Publishing family and taking up a Topical Editor position at Optics Letters. Matthew's purview will encompass the areas of Multiple Scattering; Microscopy; Polarization Optics and Polarimetry; Surface Plasmonics and Nanoparticles; Microresonators and Nanophotonics; Biosensors; Imaging and Focusing Theory and Information Theory. He looks forward to working with all the staff at OL.

21 Sep 2023: We currently have three open research fellow positions in the Optical Theory Group, to support new and ongoing research efforts in the areas of modelling of complex optical networks, informatics in digital molecular assays and computational imaging. Click the links to get more information and apply. Feel free to get in touch for more information.

16 Aug 2023: We are excited to welcome a new masters student to the group. Shiqi Tang will be joining to work on modelling complex optical networks and their optical properties.

14 Aug 2023: The OTG team is growing! We welcome Dr Aswani Natarajan as the latest addition to the group. She will be joining our efforts at IDMxS working on electromagnetic modelling of optical imaging and sensing systems.

8 Aug 2023: Today we got some good news! Our Tier 1 grant on complex optical networks was granted. We thank the Ministry of Education and NTU for their support. We will be recruiting for this project, so watch this space for upcoming job alerts or check our vacancy listing.

3 Aug 2023: The final version of Niall's PhD thesis, on "Random matrix modelling of polarised light scattering in disordered media" is now available in its full glory. You can read it here.

3 Aug 2023: The deadline for submission for the Sensors Special Issue on "Advanced Sensing and Imaging Technologies" that Zahid Yaqoob from MIT and Matthew Foreman are guest editing has been extended to 30 November 2023. Please get in touch if you are interested in submitting as some fee discounts are available. We invite contributions in fields including, but certainly not limited to, recent developments in optical bio-, chemical or physical sensors, molecular detection, microscopy, fluorescence, deep-tissue or computational imaging and their applications in healthcare, nanotechnology, metrology, environmental monitoring, defence and/or astronomy. Full details can be found here.

28 Jul 2023: We attended the Computational Imaging workshop today organised by Prof. Ling at NTU. The talks given by Renjie Zhou and Nansen Zhou, and the extensive tutorial session by Prof. George Barbastathis were all very interesting.

21 Jul 2023: We have a new opening for a Research Fellow at the Insitute for Digital Molecular Analytics and Science (IDMxS). The position will focus on informatics and decision making in diagnostics (see here for details and to apply). Applications close on 4th August and should be made via the NTU Workday portal. Feel free to get in touch if you have questions.

7 Jul 2023: Looking for a PhD in theoretical optics, information theory or biosensing? Why not consider joining the Optical Theory Group in EEE at Nanyang Technological University in Singapore? PhD intakes are in January or August and OTG has scholarships available! Further details can be found here. Some available projects are listed here, but we are always open to discuss possible research with you to ensure the best fit. Please contact Matthew Foreman for further information.

7 Jul 2023: The deadline to apply for a PhD position (January 2024 intake) through the IDMxS Interdisciplinary Graduate Programme (IGP-IDMxS) is approaching fast. For those that are interested submit your application via this link before 31st July. For more details on the eligibility and information on the programme, click here. We recommend you get in touch with Matthew Foreman before applying to discuss projects available within the Optical Theory Group and for further application guidance.

3 May 2023: Together with Zahid Yaqoob, Matthew Foreman is guest editing a new Special Issue in Sensors MDPI on "Advanced Sensing and Imaging Technologies". Please consider submitting an original article or review. We invite contributions in these fields including, but certainly not limited to, recent developments in optical bio-, chemical or physical sensors, molecular detection, microscopy, fluorescence, deep-tissue or computational imaging and their applications in healthcare, nanotechnology, metrology, environmental monitoring, defence and/or astronomy. The deadline for submissions is 20 August 2023. Full details can be found here.

20 Apr 2023: Niall successfully defended his PhD thesis today after a long 4+ hour viva! Congratulations on the hard work. His thesis centers around developing a numerical modelling technique describing propagation of polarised light through disordered media, and will be available soon. Thanks also to his two examiners. Prof. Jacopo Bertolotti from University of Exeter and Dr. Eva-Maria Graefe from Imperial College.

2 Apr 2023: It is time again for the Focus on Microscopy conference. This year Zhonghe is in Porto, Portugal to present his poster on polarisation sensitive phase contrast microscopy as a route to readout of polarisation multiplexed optical data storage. If you want a preview of his poster you can view it here. Good luck Zhonghe!

30 Mar 2023: We are now recruiting for two Research Fellow positions at the Insitute for Digital Molecular Analytics and Science (IDMxS) in Singapore. We have a theoretical position focusing on nanophotonics (see here or here) and an experimental position building nanoparticle and SERS based microscopes (see here or here). Applications close on April 13.

1 Mar 2023: The group has finally moved! After saying his goodbyes at Imperial College, Matthew has started his new role as Assistant Professor at Nanyang Technological University in Singapore. Niall Byrnes will be joining him soon to continue his research on modelling propagation of polarised light in random media. PhD positions are still available so please check them out if you fancy joining the group.

1 Feb 2023: After a final push Niall has just submitted his PhD thesis on random matrix modelling of polarised light scattering in disordered media! A big congratulations on what is an excellent piece of work.

14 Dec 2022: Our latest paper in Waves in Random and Complex Media has just gone live online. In it we describe a new random matrix modelling technique to describe propagation of polarized light through a random scattering medium. It is open access, so check it out now!

21 Oct 2022: After 7.5 years at Imperial College, the group is moving! As of March 2023, Matthew will take up an Assistant Professor position at Nanyang Technological University in Singapore. Matthew's appointment is in the School of Electrical and Electronic Engineering (EEE) and he will be working closely with the Institute for Digital Molecular Analytics and Science (IDMxS).

21 Oct 2022: We have funding available for a number of PhD positions based at NTU Singapore. A list of currently available projects can be found here. Contact Matthew Foreman if you are interested in joining the team or want more information.

30 Aug 2022: Photon22, held in Nottingham this year, was an interesting and diverse conference, drawing together many experts on sensing and polarization optics from around the UK and beyond. We were there presenting our work on single particle plasmonic sensing.

3 Aug 2022: Niall presented his poster on modelling polarised light scattering in disordered media with a random matrix approach at the 2022 Complex Nanophotonics Science Camp. Thanks to all for their interest and questions.

8 Jun 2022: The London Plasmonics Forum was held at Imperial College this year. There was a diverse range of talks. Matthew was there presenting a poster on our recent single particle plasmonic sensing work. It was good to catch up with some old colleagues and meet some new ones.

1 Jun 2022: We are happy to welcome Haomin back to the group. After succesfully completing his BSc project with us he will continue his work looking at point spread function engineering in polarisation microscopes as a summer research project.

20 May 2022: Check out our latest arXiv preprint which details our new random matrix model capable of describing anisotropic scattering of polarised light in thick scattering media. We enforce a number of physical constraints on randomly generated scattering matrices and can describe polarisation dependent media such as suspensions of chiral particles.

13 Apr 2022: It was nice to get back to the Focus on Microscopy conference this year after a few years away. Smaller conference than usual but still a good number of interesting high quality talks. Thanks to the organising committee.

20 Feb 2022: We have added a new page to our group website, where you can view some of our recent posters that have presented at a variety of conferences and workshops. Click here to take a look now.

17 Feb 2022: Congratulations to Joel for successfully defending his PhD thesis on random scattering of surface plasmons for biosensing. Read it here. Thanks also to his examiners Prof. Thomas Søndergaard and Prof. Martin McCall.

8 Jan 2022: The group welcomes its latest additions: Haomin Zhang and Sun Yang, who will be undertaking their BSc final year research project with us.

17 Dec 2021: Well done to Joel for submitting his PhD thesis today! With all the turbulence of the pandemic this is a major achievement and required a lot of hard work! You have earnt a good break before your viva. Congratulations!

15 Dec 2021: After some unfortunate covid delays, our experimental collaboration with Prof. Donghyun Kim and Hongki Lee from Yonsei University has born fruit! Read all about our work demonstrating single label free nanoparticle detection using random scattering of surface plasmons on a random nanoisland sensor, in our paper just published in Nanotechnology.

8 Dec 2021: Due to recent covid outbreaks in China, both the ICOEO and PIERS conferences are postponed. This means you will unfortunately have to wait until 25-27 March 2022 and 25-29 April 2022 respectively to see talks from Niall and Matthew.

15 Oct 2021: You can read our latest preprint describing recent experimental results from our collaboration with Prof. Donghyun Kim of Yonsei University and his group, showing single particle detection using random plasmon scattering.

29 Sep 2021: Our latest article on the polarisation properties of a restricted class of random scattering media has finally been published in Optics Communications.

6 Sep 2021: Matthew gave a keynote talk as part of the IOP Stochastic Electromagnetism and Coherence Conference discussing our recent work on modelling of polarisation imaging through scattering media. There was a wide diverse range of speakers at this interesting event. Many thanks to the organisers for the invitation.

2 Aug 2021: The second of our papers discussing enhancing single particle detection using multiple scattering has just been published in Physical Review Research. This article focuses on the particular role absorption can play on achievable enhancements.

21 Jul 2021: Joel will be presenting his recent work on tracking single particles using random scattering at the OSA Optical Sensors and Sensing Congress tomorrow as part of the Nanophotonics and Plasmonics Biosensors III session. If you are attending then check out his talk!

19 Jul 2021: Our recent theoretical article on enhancing single particle detection using multiple scattering has just been published in ACS Photonics. Well done to Joel for his hard work on this!

11 Jun 2021: Matthew has been invited to become a Editor for the Sensing and Imaging Section of the MDPI Sensors journal.

12 May 2021: New collaborative paper has just been published in Optics Letters in which Harald Schwefel and his group from the University of Otago in New Zealand experimentally realise predictions we made of anomalous resonance shifts in optical resonators.

7 May 2021: We have just submitted two new preprints to arXiv on our work on multiple scattering of surface plasmons as a means to enhance single particle detection. You can read them here and here.

2 May 2021: Joel gave a nice talk as part of the Photonics seminar series about his PhD results so far.

30 Apr 2021: We have been successful in our funding application. The Royal Society has extended Matthew's University Research Fellowship for a further 3 years. The project includes study of polarization imaging through scattering media and fundamental analysis of such systems from an information theoretic perspective.

29 Apr 2021: Joel has been accepted to give a talk at the OSA Optical Sensors and Sensing Congress. Congratulations!

28 Apr 2021: Matthew attended the second session of the Waves in Time-Varying Media workshop. An interesting set of talks, just as with the first session on the March 31st. Thanks to the organising committee.

10 Feb 2021: Niall's paper looking at various physical symmetry constraints imposed on vector scattering and transfer matrices has just been published in Physical Review Research.

9 Oct 2020: Cheryl Seow has just had her paper published in Optics Letters. She reports on her PhD work, co-supervised by Peter Török, looking at using single pixel imaging for polarimetric studies through thick strongly scattering media.

5 Oct 2020: A new member has joined the group. We welcome Zhonghe Feng who also works jointly in the group of Prof. Mark Neil. As part of a Microsoft funded project, he will focus on building and modelling a system capable of measuring 3D birefringence distributions.

15 Apr 2020: Despite current coronavirus restrictions Cheryl has successfully defended her PhD thesis on single pixel polarimetric imaging through scattering media. Congratulations - well deserved! Thanks also to her PhD examiners Dr. Peter Munro and Prof. Chris Dunsby. Read her thesis here.