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Rochester Lecture archive

2023

  Title of the talk
Rochester lecture 2023 image

Smart microscopy for everyone with open source hardware

Speaker
Dr. Richard Bowman
Description

In an ideal world, any published experiment could be reproduced exactly from the scientific record, but in practice this is often hard or impossible. The OpenFlexure project uses open source hardware and software methodologies to address many of the challenges we face when sharing a complicated instrument.

Designs, instructions, and code for the OpenFlexure Microscope are shared under open licenses, using tools and platforms developed for open software. This open documentation has been used to replicate the microscope by hundreds of people, in over 40 countries, in settings from hack spaces to super-resolution imaging labs.

The OpenFlexure Microscope is a digital optical microscope, complete with high resolution 3-axis motorised positioning and configurable imaging modes. On its own, it is a reliable instrument for bright field or fluorescence microscopy, but it is also a platform for more complicated imaging techniques, where it provides an easy way to include the fundamentals of a microscope (imaging optics and mechanical design) in a larger instrument. We have included interfaces for automation and integration of the OpenFlexure Microscope into experiments and protocols, and are now working on higher-level software tools to ensure reliable calibration and operation. Much of this builds on our “Internet of Things” architecture, where an embedded computer in the microscope makes it easier to use and to program.

This talk will cover both the technical achievements of the OpenFlexure Microscope, and the community that has grown up around the design. I will touch on how we have embraced open development, and on how that has helped the project grow in reach and impact. Our use of software tools to support hardware development has led to the development of bespoke tools for documentation, and libraries for instrument control. I will discuss how the tools and approaches used in the OpenFlexure Project can be generalised to other experimental science projects, to improve both reproducibility and accessibility.

About the Speaker

Dr Richard Bowman is a Royal Society University Research Fellow and Reader specialising in microscopy and open hardware. His research group is at the heart of the OpenFlexure project, which he started in 2015 while a research fellow in Cambridge. His first independent position was at the University of Bath from 2017, where he held several GCRF projects with Tanzanian collaborators investigating the use of locally produced microscopes for malaria diagnostics. He moved to the University of Glasgow in 2022, where his lab continues to develop the OpenFlexure microscope, work on a range of problems in microscopy, and push forward open hardware and software as a vehicle for making experimental science more reproducible.

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2022

  Title of the talk
Image of Prof. Heather Lewandowski and the JILA and Colorado University logos

Watching chemical reactions happen one molecule at a time

Speaker
Prof. Heather Lewandowski
Description

Control over the quantum states of atoms and molecules can lead to a fundamentally new understanding of how these particles interact and react. This knowledge has the potential to impact our ability to probe processes in planetary atmospheres and in the interstellar medium, as well as relevant terrestrial process such as combustion. Experimental techniques developed for control and measurement of atoms is now being used to study more and more complex molecules.

We study these rich systems at low temperatures where we can trap and examine their properties for many minutes, as compared to small fractions of a second in standard experiments. Using these cold, trapped molecular ions, we investigate mechanisms of ion-molecule reactions to gain insights into the mechanisms driving these processes.

2022 Rochester Lecture poster

About the Speaker

Prof. Heather Lewandowski received her B.S. in physics from Michigan Tech in 1997 and her Ph.D. in physics from the University of Colorado in 2002. She was then an NRC Postdoctoral fellow at the National Institute of Standards and Technology in Boulder. She is currently a professor and associate chair of physics at the University of Colorado, and a fellow of JILA. She leads two research programs, one in experimental molecular physics, and the other in physics education research. Her molecular physics research efforts focus on studying interactions and reactions of cold, chemically important molecules and ions. Her physics education research program studies ways to increase students’ proficiency in scientific practices such as using models and quantitative reasoning in experimental physics.  

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2019

 Title of the talk


From left: Professor Nigel Glover - Head of the Physics Department, Prof. Jun Ye - 2019 Rochester speaker, Dorothy Sills, David Sills, Prof. Stuart Corbridge - Vice-Chancellor, and Prof. Simon Cornish - Head of the Quantum Light and Matter group
   

Quantum Matter and Atomic Clocks

Speaker
Prof. Jun Ye
Description

Relentless pursuit of spectroscopy resolution has been a key driving force for important scientific and technological breakthroughs, including the invention of laser and the creation of cold atomic matter. The most stable lasers now maintain optical phase coherence over tens of seconds.

Meanwhile, precise quantum state engineering of individual atoms in both internal and external degrees of freedom has led to the unprecedented measurement performance for time and frequency. The use of many atoms not only enhances counting statistics, but also provides a powerful tool to protect against systematic uncertainties.

At the core of the new three-dimensional optical lattice clock is a quantum gas of fermionic atoms spatially configured to guard against motional and collisional effects. Such precise control of light-matter interactions is fostering new capabilities to probe fundamental and emerging phenomena.

About the Speaker

Jun Ye is a Fellow of JILA and a Fellow of NIST. He is a member of the National Academy of Sciences, a Fellow of the American Physical Society, and a Fellow of the Optical Society of America. His research focuses on the frontiers of light-matter interactions and includes precision measurement, quantum physics and ultracold matter, optical frequency metrology, and ultrafast science. He has co-authored over 300 scientific papers and has delivered over 500 invited talks.

Awards and honors include N.F. Ramsey Prize (APS), Rabi Award (IEEE), US Presidential Rank (Distinguished) Award, three Gold Medals from the U.S. Commerce Department, Foreign Member of the Chinese Academy of Sciences, Frew Fellow of the Australian Academy of Science, I.I. Rabi Prize (APS), European Frequency and Time Forum Award, Carl Zeiss Research Award, William F. Meggers Award and Adolph Lomb Medal from the Optical Society of America, Arthur S. Flemming Award, Presidential Early Career Award, Friedrich Wilhem Bessel Award of the Alexander von Humboldt Foundation, and Samuel Wesley Stratton Award, and Jacob Rabinow Award from NIST. Group web page, http://jila.colorado.edu/YeLabs/.

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2018

 Title of the talk

Quantum optics with artificial atoms

Speaker
Prof. Pascale Senellart
Description

Quantum light is a key resource for the development of quantum enhanced technologies such as secure communications, quantum networks, distributed quantum computing, metrology, etc. The development of these technologies requires light sources emitting single photons in a pure quantum state as well as efficient photon-photon gates. Such sources and gates can be obtained making use of the single-photon sensitivity of an atomic transition.

We study artificial atoms in the form of semiconductor quantum dots to develop building blocks for optical quantum technologies. We use the tools of opto-electronics and nanotechnology to fabricate close to ideal atom-photon interfaces, where a single artificial atom interacts with a single mode of the optical field. We show that cavity quantum electrodynamics allows to largely isolate the artificial atoms from all sources of decoherence such as charge noise and crystal vibrations. We obtain bright solid-state sources of single photons with very high quantum purity that allow scaling-up intermediate quantum computing tasks. We have also made progresses toward the development of efficient two-photon gates, with devices performing as nonlinear switches at the single-photon level.

About the Speaker
Professor Pascale Senellart is from the Center for Nanoscience and Nanotechnology, Paris Sud and Paris Saclay Universities

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2017

 Title of the talk

Poster for the 2017 Rochester lecture

 

Group photo of Prof Knight with Durham academics and members of the Rochester family

Quantum Technology for a Networked World

Speaker
Prof. Sir Peter Knight FRS
Description

Quantum Physics has focused on light, matter and their interaction, from the early days of quantum mechanics right down to the present day. Much of this work has concentrated on the nature of quantum correlations beyond what is allowed classically.

Progress in identifying, generating and characterizing nonclassical states has been spectacular. Quantum Information Science in part has grown out of this progress: the quantum world allows information to be encoded, manipulated and transmitted in ways quite different from classical physics.

And now we are seeing the transition to technology, applying these insights in spectacular new ways.


Parallelism and entanglement, the characteristic features of the quantum world, enable us to perform precise measurements and to undertake information processing tasks which are peculiar to the quantum world: secure encryption, teleportation of quantum states and the speed up of certain classes of algorithms.

The 21st Century has seen the emergence of a networked world, connected by global fibre-optic communications and mobile phones, with geo-location provided through GPS, and all this has changed our lives more dramatically than at any time since the industrial revolution. Quantum-enabled technology is at the heart of this change.

I will describe these developments and how the UK has invested substantially in the basic science and its exploitation. Some of these include communication systems immune to GPS jamming (of real importance for global security), as well as quantum sensors for medical applications (including cardiography, neurophysiology, etc), sensitive magnetometry, gyros, and geophysical surveying.

About the Speaker

Professor Sir Peter Knight is Senior Research Investigator in the Physics Department at Imperial College and Senior Fellow in Residence at the Kavli Royal Society International Centre at Chicheley Hall. He retired in September 2010 as Deputy Rector (Research) at Imperial College where he was responsible for the College’s research strategy. He is President of the Institute of Physics (from 2011-2013). He was a member of the Imperial College Management Board and Council, and Professor of Quantum Optics. He was knighted in the Queen’s Birthday Honours List in 2005 for his work in optical physics. He was until 2008 Principal of the Faculty of Natural Sciences at Imperial College London. He was Head of the Physics Department, Imperial College London from 2001 to 2005. Peter Knight is a Past-President of the Optical Society of America and was for 7 years a member of their Board of Directors. He is a Director of the OSA Foundation. He was coordinator of the SERC Nonlinear Optics Initiative, past-chair of the EPS Quantum Electronics and Optics Division and Editor of the Journal of Modern Optics from 1987 to 2006. He is Editor of Contemporary Physics and serves on a number of other Editorial Boards. He is a Thomson-ISI “Highly Cited Author.”

 

Sir Peter was until December 2010 chair of the Defence Scientific Advisory Council at the UK Ministry of Defence, remains a Government science advisor and was a Council member of the Science and Technology Facilities Council until 2012. Sir Peter was also Chief Scientific Advisor at the UK National Physical Laboratory until the end of 2005. His research centres on theoretical quantum optics, strong field physics and especially on quantum information science. He has won a number of prizes and awards including the Thomas Young Medal and the Glazebrook Medal of the Institute of Physics, the Ives Medal of the OSA and the Royal Medal of the Royal Society. He has been a Visiting Professor at the University of Louvain-la-Neuve, a Humboldt Research Award holder at the University of Konstanz and a Visiting Scholar at the University of Texas at Austin and at the University of Rochester. He is a Fellow of the Institute of Physics, the Optical Society of America and of the Royal Society. He was an elected member of Council of the Royal Society from 2005 to 2007 and was a member of their Audit Committee and chair of the Hooke Committee responsible for scientific meetings at the Royal Society. He is chair of the University Research Fellowships Ai Panel for 2010-13.

 

After his doctorate at Sussex University, Sir Peter joined the group of Joe Eberly as a Research Associate from 1972-1974 in the Department of Physics and Astronomy of the University of Rochester and at the Physics Department and SLAC, Stanford University, USA, followed by a period as SRC Research Fellow 1974-1976 at Sussex University; and in 1976 was Visiting Scientist at the Johns Hopkins University, Baltimore, USA. In 1976 he became Jubilee Research Fellow, 1976-1978 Royal Holloway College, London University, followed by an SERC Advanced Fellowship from 1978-1983, first at RHC from 1978 to 1979, transferring in 1979 to Imperial College. He has remained ever since at Imperial College (apart from very frequent visits to the USA), first as a Lecturer 1983-1987, then Reader 1987-1988 and Professor since 1988.

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2016

 Title of the talk

 

 Image of poster for the Rochester Lecture 2016

 

Using Physics to Change the World - A Personal Story

Speaker
Dr John C. Taylor OBE
Description
“Time is not on your side, it’s rather scary, so I changed the cuddly image of a Walt Disney grasshopper into a rather frightening time eater. I thought it would be fun if in a minute he slowly opened his jaws wider and wider, and on the 59th second of every minute he went crunch, got that minute, chewed it up and swallowed it so you could never get it back.”
About the Speaker

Inventor and horologist Dr John C Taylor OBE has been awarded the prestigious Harrison Medal by the Worshipful Company of Clockmakers, the oldest horological institution in the world - something which has only been awarded to six other people. It commemorates outstanding achievements in propagating knowledge of the history of clockmaking and its appreciation, and is named after John Harrison, the renowned inventor of the marine chronometer. Previous recipients include Durham's own renowned astronomer and physicist Sir Arnold Wolfendale FRS, horologist Jonathan Betts MBE and horologist David Thompson. Regarded as one of the world’s leading experts in the work of John Harrison, Dr Taylor has lectured around the world and alongside fellow Harrison Medal recipient Dava Sobel, who wrote the book Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time about John Harrison. John Harrison was an early horological pioneer, and his ‘marine chronometer’ was the first clock accurate enough to be used for navigational purposes.

 

Dr Taylor was born in Buxton in Derbyshire in 1936 and attended King William School on the Isle of Man before studying Natural Sciences at Cambridge University. After finishing his education he took a job at Otter Controls, founded by his father, and began working in bi-metal. His work with these controls led to Dr Taylor designing the thermostat systems that are used in almost two billion kettles and small household appliances. Dr Taylor left Otter Controls to build his own company, Strix, which holds four Queen’s Awards. Three are for Export and one is for Innovation, granted for his 360-degree cordless kettle connector, which is used every day by almost every household and workplace in the UK. As well as being one of the world’s most prolific inventors, Dr Taylor has also conducted a lot of research into the subject of horology. He is one of the world’s leading experts in the work of John Harrison, an early pioneer of clocks and time-keeping. This led him to design and help build the Corpus Chronophage, a three metre-high clock that is displayed in an exterior wall of the Corpus Christi College building at Cambridge University.

 

Dr Taylor has one of the world’s most comprehensive collections of early English clocks, including one of only three surviving John Harrison longcase clocks still working. Four of his items are currently being exhibited as part of the National Maritime Museum’s Ships, Clocks & Stars Exhibition, which has been transferred to Mystic Seaport, the USA’s leading maritime museum. His interest in clocks extends beyond appreciation and study – his admiration for John Harrison led him to design and build the Corpus Chronophage, a three-metre high clock that is displayed in an exterior wall of his alma mater: Corpus Christi College, Cambridge. It was unveiled in 2008 by world-renowned physicist Stephen Hawking. Dr Taylor is perhaps best known for having created the bimetal thermostat controls inside electric kettles and other small household appliances. To date, over two billion of these thermostats have been used around the globe. He has over 400 patents to his name, making him one of the world’s most prolific inventors. Bimetal itself was invented by his hero John Harrison.

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2015

 Title of the talk
 

 

Group photograph of Miles Padgett with the Head of the Physics Department, Mr & Mrs Rochester and assorted academics

Front row from left: Sylvia Rochester, Tony Rochester, Prof Miles Padgett (guest speaker), Prof Simon Morris (Head of Department), Prof Charles Adams
Back row left to right: Prof Gordon Love, Prof David Bloor, Prof Brian Tanner, Prof Dick Abram 

Ghost Imaging: new approaches to imaging inspired by Quantum Physics

Speaker
Prof. Miles Padgett FRS
Description

Cameras are often marketed in terms of the number of pixels they possess – the more pixels the “better” the camera. Rather than increasing the number of pixels, as part of the UK's Quantum Technology Network, we ask the question “how can a camera work with a single pixel?”.

This talk will link the field of computational ghost imaging to that of single-pixel camera's explaining how spatial structuring of either the illumination or imaging system means that image and video reconstruction can be achieved using just a few photodiodes.

The talk will also show how the correlations that make quantum mechanics "spooky" can be utilised to create visible light images even when the object has only been illuminated by a small number of infra-red photons.

Both approaches are particularly useful for imaging at wavelengths where detector arrays are either very expensive or unobtainable.

About the Speaker
The talk was given by Professor Miles Padgett FRS of Glasgow University, where he is Vice-Principal for Research and the Kelvin Chair of Natural Philosophy in the School of Physics and Astronomy. In 2001 he was elected to Fellowship of the Royal Society of Edinburgh, and in 2014 he was elected as a Fellow of the Royal Society. Prof Padgett was awarded the UK Institute of Physics, Optics and Photonics Division Prize for his research achievements in optical angular momentum and applied optical sensors.

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2014

 Title of the talk

Group photo with the 2014 Rochester speaker Ian Walmsley

The 2014 Rochester Lecture guest speaker, Professor Ian Walmsley (pictured centre), with from left:
Tony Rochester, Simon Gardiner, Martin Ward (HoD), Dorothy Sills, Ifan Hughes (behind),
Sir Arnold Wolfendale, David Sills.

Building Quantum Machines out of Light

Speaker
Prof. Ian Walmsley
Description

Ian Walmsley looks in his lecture at how light has the remarkable capacity to reveal quantum features under ambient conditions, making exploration of the quantum world feasible in simple laboratory experiments. Further, the availability of high-quality integrated optical components makes it possible to conceive of large-scale quantum states by bringing together many different quantum light sources and manipulating them in a coherent manner and detecting them efficiently.

By this route, we can envisage a scalable photonic quantum network, that will facilitate the preparation of distributed quantum correlations among many light beams. This will enable a new regime of state complexity to be accessed - one in which it is impossible using classical computers to determine the structure and dynamics of the system.

This is a new regime for scientific discovery, but such networks also have a practical purpose: the same complexity of big quantum systems may be harnessed to perform tasks that are impossible using known future information processing technologies. For instance, ideal universal quantum computers may be exponentially more efficiently than classical machines for certain classes of problems, and communications may be completely secure. Photonic quantum machines will open new frontiers in quantum science and technology.

About the Speaker

Professor Ian Walmsley is the Hooke Professor of Experimental Physics, Head of Atomic and Laser Physics and Professorial Fellow of St Hugh’s College, Oxford. He is a fellow of the Royal Society and is also shortly to be appointed Oxford University’s Pro-Vice-Chancellor for Research. Professor Walmsley was educated at Imperial College, London, and the Institute of Optics, University of Rochester, New York.

Professor Walmsley has made a number of contributions to the fields of quantum optics and ultrafast optics, including pioneering experimental work in areas as diverse as quantum state tomography and ultrashort pulse characterization. His work has had a broad impact across areas from coherent control to quantum information processing. In particular he has developed methods and concepts applying ultrashort light pulses to the study of nonclassical phenomena in both atomic and optical physics, developing widely used methods for the characterization of both quantum and classical wave fields, which have broad implications across a range of areas from dynamical spectroscopy to quantum state measurement.

He has led two academic programs in the USA and UK, most recently the Sub-Department of Atomic and Laser Physics. He is a Science Delegate for Oxford University Press and served on the Physics RAE panel in 2008.

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2012

 Title of the talk

From Einstein to Wheeler: wave particle duality for a single photon

Speaker
Prof. Alain Aspect
Description
The lecture was very well attended and everyone left inspired by an enthusiastic presentation on the nature of light. The Rochester family attended and greatly appreciated the lecture and the audience it attracted. Professor Aspect was impressed with the size and quality of the department and the interest in the lecture.
About the Speaker

Alain Aspect is noted for his experimental work on quantum entanglement. He is a graduate of the École Normale Supérieure de Cachan (ENS Cachan). He passed the 'agrégation' in physics in 1969 and received his master's degree from Université d'Orsay. In the early 1980s he performed the elusive "Bell test experiments" that showed that Albert Einstein, Boris Podolsky and Nathan Rosen's reductio ad absurdum of quantum mechanics, namely that it implied 'ghostly action at a distance', did in fact appear to be realised when two particles were separated by an arbitrarily large distance.

 

A correlation between their wave functions remained, as they were once part of the same wave-function that was not disturbed before one of the child particles was measured. If quantum theory is correct, the determination of an axis direction for the polarization measurement of one photon, forcing the wave function to 'collapse' onto that axis, will influence the measurement of its twin. This influence occurs despite any experimenters not knowing which axes have been chosen by their distant colleagues, and at distances that disallow any communication between the two photons, even at the speed of light. Aspect's experiments were considered to provide overwhelming support to the thesis that Bell's inequalities are violated in its CHSH version, providing strong evidence that a quantum event at one location can affect an event at another location without any obvious mechanism for communication between the two locations.

 

This has been called "spooky action at a distance" by Einstein (who doubted the physical reality of this effect). However, these experiments do not allow faster-than-light communication, as the events themselves appear to be inherently random. After his works on Bell's inequalites, he turned toward studies of laser cooling of neutral atoms and is now mostly involved in Bose–Einstein condensates related experiments. Aspect was deputy director of the French "grande école" SupOptique until 1994. He is a member of the French Academy of Sciences and French Academy of Technologies, and professor at the École Polytechnique. In 2005 he was awarded the gold medal of the Centre national de la recherche scientifique, where he is currently Research Director.

 

The 2010 Wolf Prize in physics was awarded to Aspect, Anton Zeilinger and John Clauser. October 7, 2013, Aspect was awarded the Danish Niels Bohr International Gold Medal. In 2013 he was also awarded the Balzan Prize for Quantum Information Processing and Communication.

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2011

 Title of the talk
Image of Sylvia Rochester, Prof Richard Abram, Tony Rochester, David Sills, Prof. Jeremy Baumberg FRS, Alastair Edge, Dorothy Sills, Prof Martin Ward.From left: Sylvia Rochester, Prof Richard Abram, Tony Rochester, David Sills, Prof. Jeremy Baumberg FRS, Alastair Edge, Dorothy Sills, Prof Martin Ward. 

Squeezing light into nanometre cages: putting the nano into photonics

Speaker
Prof. Jeremy J. Baumberg
Description
Generations of students have been taught that light can be focussed down only as tightly as a spot of order of its wavelength. This several hundred nanometer scale limit would imply that nano-scale active elements cannot interact strongly with light. However this turns out to be untrue, and we are able to demonstrate the localisation of light tighter than 1nm. This has two principal benefits: spectroscopy can be used to probe such nano-scale architectures containing individual objects, and light can be concentrated to high intensity in ultra-small volumes. Both these have utility in a variety of new applications, which open up other areas of science.
About the Speaker
Jeremy Baumberg of the NanoPhotonics Centre, University of Cambridge, is a leader in nanoscience and nanotechnology, working for much of his career at the interface between academia and industry. He has led interdisciplinary nano-centres at the Universities of Cambridge and Southampton, and developed novel devices within Hitachi, IBM, his spin-offs Mesophotonics and Base4. He is widely recognised as a leading innovator in Nano, with most recent awards being the Institute of Physics Young Medal (2013), Royal Society Fellowship (2011) and Royal Society Mullard Prize (2005).

 

Professor Baumberg is recognised for his development of a number of seminal experimental techniques in condensed matter physics. His pioneering work on the ultrafast dynamics of magnetic semiconductors was a major stimulus to the field of spintronics. His experiments on coherent control in solids initiated much of the topical area of quantum information processing in semiconductors, and his work on semiconductor micro-cavities initiated the field of polariton optical amplifiers and condensates. His most recent activity, developing nanoscale-structured metamaterials, is revealing a host of strikingly novel and highly exploitable optical properties, as eg in photonic crystals, for which he was awarded the Mullard Prize.

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2010

 Title of the talk

(from left - right) David Sills, Sir Arnold Wolfendale, Dorothy Sills, Prof Charles Adams, Prof Michael Charlton, Prof Martin Ward, Tony Rochester, Dr Alistair Edge, Prof David Flower, Dorothy Rochester and Dr Gordon Love

Antimatter: From Imagination to Application - and back

Speaker
Prof. Michael Charlton
Description
Antimatter was predicted and discovered in the 1930's. The positron, the antimatter counterpart to the electron, has since numerous applications in material science, engineering and medicine, making use of its annihilation with electrons.

 

Recently, Physicists have learnt how to create atoms of antihydrogen under controlled conditions in a vacuum. These experiments were discribed as well as the motivation for undertaking them. This involved one of natures great conundrums: the absence of bulk antimatter in the current epoch of the universe.
About the Speaker

Professor Michael Charlton is an experimental atomic physicist, with interests in positrons, positronium and antihydrogen and leads Swansea University's involvement in an international project on antimatter called ALPHA. ALPHA was the first group to demonstrate trapping of antihydrogen in a neutral atom trap and to observe a resonant quantum transition in the anti-atom. He has made contributions to many aspects of the development of physics with low energy positrons and helped to establish positronium beam physics. Since the mid-1980’s he has pioneered the field of antihydrogen physics. 

 

Charlton was a founder member of the ATHENA collaboration that first produced cold antihydrogen and is now a member of the ALPHA collaboration. Every few weeks he travels to Cern in Switzerland to carry out experiments and develop his research into the complex world of particle theory on what is a massive collaboration of around 40 scientists from institutions ranging from the University of California, Berkeley to the Federal University of Rio de Janeiro in Brazil. Their purpose is to research how to make and then store antimatter in order to research and study its properties.

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