David Andrews first joined UEA as a Lecturer, following doctoral studies in Chemistry, and a Research Associate position in the Department of Mathematics, both at University College London. At UEA, he gained a Chair in Chemical Physics in 1996. He has twice held Visiting Fellowships at University of Canterbury in New Zealand, and twice at the University of Western Ontario in Canada. Professor Andrews is a Fellow of the Royal Society of Chemistry, Fellow of the Institute of Physics, Fellow of the Optical Society of America, and a Fellow of SPIE, the International Society for Optical Engineering. He was a Member of the Executive Committee of SPIE from 2019-2022, and served as President in 2021.

Professor Andrews leads the nanophotonics and quantum electrodynamics research group at UEA. The interests of his research group broadly concern developing the theory of molecular interactions - with each other, and with light - in terms of quantum electrodynamics (QED). Quantum electrodynamics is essentially the study of how matter interacts with light, treating both matter and light quantum mechanically. The QED group at UEA has been at the forefront in applications ranging from spectroscopy and nonlinear optics to the intermolecular transport of energy. Present research topics fall into four main areas: Molecular energy transfer and light harvesting; Nonlinear optics and photonics; Structured light and optical vortices; Laser-induced optical binding and inter-particle forces. The group enjoys strong international links, particularly with groups in Australia, Canada, Lithuania, New Zealand and the United States.

Prof. Andrews has over 400 research papers and also more than twenty books to his name, including as author an Introduction to Photon Science and Technology, and as Editor-in-Chief a four-volume Wiley series on Photonics, and a five-volume Elsevier series entitled Comprehensive Nanoscience and Nanotechnology. He serves on the Editorial Boards of several international journals.

Selected Publications (for a fuller listing click the PUBLICATIONS tab at the top of the screen)

D.L. Andrews.
Symmetry-based identification and enumeration of independent tensor properties in nonlinear and chiral optics.
J. Chem. Phys. 158, 034101 (2023).
DOI: 10.1063/5.0129636

K.A. Forbes, D.S. Bradshaw and D.L. Andrews.
Optical binding of nanoparticles.
Nanophotonics 9, 1-17 (2020).
DOI: 10.1515/nanoph-2019-0361

D.S. Bradshaw, K.A. Forbes and D.L. Andrews.
Quantum field representation of photon-molecule interactions.
Eur. J. Phys. 41, 025406 (2020).
DOI: 10.1088/1361-6404/ab7028

D.L. Andrews, D.S. Bradshaw, K.A. Forbes and A. Salam, A.
Quantum electrodynamics in modern optics and photonics: tutorial.
J. Opt. Soc. Am. B 37, 1153-1172 (2020).
DOI: 10.1364/JOSAB.383446

J. Wade, J.R. Brandt, D. Reger, F. Zinna, K.Y. Amsharov, N. Jux, D.L. Andrews and M.J. Fuchter.
500‐fold amplification of small molecule circularly polarized luminescence through circularly polarized FRET.
Angew. Chem. Int. Ed. 60, 222-227 (2021).
DOI: 10.1002/anie.202011745

K.A. Forbes and D.L. Andrews.
Orbital angular momentum of twisted light: chirality and optical activity.
J. Phys. Photonics, 3, 022007 (2021).
DOI: 10.1088/2515-7647/abdb06

D.L. Andrews.
Symmetry and quantum features in optical vortices.
Symmetry 13, 1368 (2021) (20 pages).
DOI: 10.3390/sym13081368

L. Ohnoutek, H.-H. Leong, R.R. Jones, J. Sachs, B.J. Olohan, D.-M. Rasadean, G.D. Pantos, D.L. Andrews, P. Fischer and V.K. Valev.
Optical activity in third-harmonic Rayleigh scattering: a new route to measuring chirality.
Laser Photonics Rev. 2100235 (2021)
DOI: 10.1002/lpor.202100235

 

 

UEA

1999 – present Professor of Chemical Physics (since 1996)
1996 – 1999 Dean of Chemical Sciences
1994 Reader
1991 Senior Lecturer
1979 Lecturer

Royal Institution

1978 Science Research Council Postdoctoral Fellow

University College London

1976 - 1978 Associate Research Assistant, Department of Mathematics and Honorary Research Associate, Department of Chemistry

The current focus of his research group is on novel mechanisms for optical nanomanipulation and switching, and light-harvesting in nanostructured molecular systems. The group enjoys strong international links, particularly with groups in Canada, Lithuania, New Zealand and the United States.

David Andrews leads research on fundamental molecular photonics and energy transport, optomechanical forces and nonlinear optical phenomena.

Current Research Areas 

• Nanomanipulation with Light
• Optical Energy Harvesting

Nanomanipulation with Light

In the early years of laser development, new possibilities began to emerge for the practical utilization of optomechanical forces to manipulate small particles. The new field evolved rapidly and by the mid-eighties it had led to the invention of optical tweezers, a technique which has since become a mainstream tool for the optical trapping and manipulation of a diverse range of particles, from living cells down to single atoms. More recently, alongside burgeoning biological applications, there has been a growing recognition of the potential for other distinctive nanotechnological applications of laser-induced forces. The activity in this area has seen a huge increase in its range, with the latest advances leading to new applications such as microviscometry. There is also considerable interest in the deployment of exquisite new beam structures for laser light; notably, the use of ‘twisted’ beams in optical tweezers can produce effects that have become known as ‘optical spanners’ that can not only trap particles but also rotate them.

In general, optomechanical forces operate on individual particles, and their action is to some extent modified by other inter-particle interactions. The fundamental character of the latter forces is very well known and, for particles separated beyond the region of wavefunction overlap, derives from dipole interactions, dispersion forces etc. Quantum mechanics provides the framework for their detailed evaluation. Recently, it has emerged from our studies based on quantum electrodynamics (QED) – a theory that designedly addresses the quantum interactions of matter with radiation – that with the throughput of intense laser light it is possible to significantly modify the form and magnitude of inter-particle coupling forces. Entirely distinct and separable from the optomechanical interactions involved in optical tweezers, these laser-induced inter-particle forces and torques are capable of generating novel patterns of particle motion determined by the intensity, polarization and other features of the laser input.

It is noteworthy that, since its original postulation, the threshold levels of intensity necessary to induce significant forces (typically megawatts per square centimetre) have become routinely available – for example by focusing the output of a standard titanium:sapphire femtosecond laser. Accordingly, the concept of laser-induced coupling forces has recently become the subject of experimental investigation, and the potential significance of the subject has soared in importance. Applications to the optical control of Bose-Einstein condensates have also been envisaged. In our current work we use a quantum electrodynamical approach to determine complete and general results for optically induced forces between chemically identical nanoparticles, also applying the results to a number of systems of current interest. Potential applications of these laser induced inter-particle forces include carbon nanotubes and nanoelectromechanical systems (NEMS).

Optical Energy Harvesting

The modern technology of optical energy harvesting has a wide variety of operational principles, the main themes of which have evolved through pursuit of better control and economy in the global utilisation of solar energy. The concept of harvesting signifies an integrated approach to the gathering from natural or environmental resources, with centralised collection and subsequent distribution according to requirements. Over the years numerous schemes have been devised for the harvesting of energy, linking sustainability with economy and, increasingly, with green issues. For the scale of the environmental resource it represents, and also the extent of its geographic availability, solar power easily outstrips its competition, and natural photosynthesis represents a process whose emulation is an obvious target. There are many well-established non-biological solutions to the energy problem, but with resolution of the detailed molecular structure and chromophore layout of the photosynthetic apparatus in a variety of living organisms, new avenues of research are leading to significant advances in the modelling, synthesis and operation of distinctly biomimetic energy harvesting materials based on photon energy pooling.

The elucidation of detailed principles for electronic energy flow in multichromophore polymers has led to a proliferation of new energy-harvesting materials tailored for a host of nanophotonic applications. Dendrimers (branched polymers) and other multichromophore assemblies prove highly effective in the capture of optical radiation as a result of their numerous antenna groups and the efficiency of resonance energy transfer (RET) in channelling optically acquired energy to an acceptor core. Energy capture and storage applications range from uses as photosensitisers in the laser photodynamic therapy of cancer, to optical devices based on organic light-emitting diodes. Increasingly, attention is being focused on applications specifically associated with a response to laser input and correspondingly high levels of irradiation. The principles of two-photon fluorescence RET are also involved in other quite distinct areas such as two-photon three dimensional imaging – a technique with well-known advantages for biological specimens due to reduced scatter, enhanced depth profiling and lower photolytic damage at the associated long wavelengths.

To expedite future progress in the design and development of optically nonlinear light-harvesting systems, it is necessary to ascertain the means of differentiating, optimizing and exploiting the mechanisms for energy capture. The mechanisms that are available to mediate energy harvesting under conditions of high photon flux differ markedly from those available at lower intensities, and a primary aim is to secure a thorough understanding of the principles that apply to systems specifically designed for operation at high levels of laser intensity, and the balance of factors that determine the favoured mechanism for each form of optical nonlinearity. Preliminary work at UEA has identified key factors which include: the chromophore architecture and distribution; energy level positioning, transition selection rules and spectral overlap; possibilities for the formation of delocalized excitons; laser coherence and excitation statistics. Present work is being linked with experiment through a new collaboration with the Institute for Lasers Photonics and Biophotonics at the State University of New York at Buffalo.

Members past & present

• Wafika Ghoul 
• Mike Harlow 
• Brad Sherborne 
• Philip Wilkes  
• Kevin Hopkins 
• Nick Blake 
• Bridget Webb 
• Alex Bittner 
• Phil Allcock 
• Andrey Demidov 
• Allison Wigman 
• Ian Hands     
• Luciana Dávila Romero
• Robert Jenkins
• Shemi Soliman
• Martin Loftus
• Sam Collins
• Gareth Daniels
• David Bradshaw
• Richard Crisp
• Shaopeng Li
• Justo Rodríguez
• Jamie Leeder

Nonlinear optics; quantum theory; spectroscopy; lasers; nanotechnology; science and religion.

Professor Andrews teaches Chemistry and Physics at all levels of Higher Education. Beyond UEA his wide teaching interests include giving public science lectures, writing textbooks, and producing web materials.

Teaching Activities