David L Andrews
Andrews is Chair of the SPIE Nanotechnology Technical Group. At UEA his
theory group conducts fundamental and applied research on optical forces,
energy transport between molecules and within macromolecules, molecular
photophysics and a range of nonlinear and quantum optical phenomena. The
studies on optical forces focus primarily on the laser manipulation of
nanoparticles such as carbon nanotubes, and the effect known as ‘optical
binding’; the research on energy transport centres on energy harvesting
in nanoscale photosystems, both natural and synthetic.
The group has
recently developed theory for optically nonlinear behaviour (multiphoton
resonance energy transfer and energy pooling) in a variety of light harvesting
materials, mostly multichromophore arrays such as dendrimers which mimic
the molecular structures operative in natural photosynthesis. Exploiting
such principles, a new basis for a new form of optical switching has also
recently been identified. The group has strong international links - particularly
with groups in Canada, the United States, New Zealand and Lithuania. For
information on other activities of the group in nonlinear optics and photonics
Stephen R Meech
group headed by Steve Meech is interested in the research applications
of lasers and nonlinear optics to probe the chemistry and dynamics of
the condensed phase and its interface, focussed on :
dynamics in complex fluids. The optical Kerr effect is used to observe
molecular motion in nanometre dispersed liquids, liquid crystal, polymers
and liquid mixtures.
in fluorescent proteins. The excited state chemistry of the chromophore
of the green fluorescent protein has been studied by ultrafast polarisation
spectroscopy and femtosecond fluorescence up-conversion.
- Laser surface
photochemistry. The photochemistry and photoelectron emission of surfaces
prepared in ultra-high vacuum are studied by steady state and time-of-flight
mass spectrometry. Studies of two-photon photoemission from ice surfaces
doped with alkali metals aim to elucidate some of the chemistry associated
with noctilucent clouds.
optics for molecular structure. The group maintains a strong interest
in applying nonlinear optics in bioimaging and surface structure determination.
Recent results include a two-photon fluorescence microscopy study of
mitosis. Also the use of second harmonic generation to probe interfaces
and organised media and (at higher order) liquid dynamics have also
Nann's research is focused on the preparation, characterisation and application
of nanomaterials in general and nanoparticles in particular.
nanoparticles of various types - noble metals, semiconductors or doped
insulators - are synthesised with wet-chemical methods. The morphologies
of the yielded particles range from spherical, rod- and wire-like to
sophisticated three-dimensional structures. The resulting nanoparticles
are further derivatised with additional inorganic surface layers like
e.g. silica, or organic ligands.
- The unique
structural, magnetic and optical properties of such nanoparticles are
invesitgated by means of transmission electron microscopy (TEM), UV/vis/PL
spectroscopy, electrochemical methods and others. The focus of interest
is on mesoscopic properties of the nanomaterials.
applications of nanomaterials are examined in collaboration with industrial
and academic partners in areas such as nanotechnology, biology and medicine.
Stephen H Ashworth
Ashworth performs high resolution spectroscopy, and other spectroscopy
applied to atmospheric chemistry, using a number of laser techniques.
The high resolution spectroscopy concentrates on the detailed molecular
and electronic structure of small transient species in the gas-phase.
In collaboration with the School of Environmental Sciences, measurements
are made of the speed of reactions involved in processing material in
the atmosphere, particularly meteoric dust and halogens released from
the sea and seashore.
interest are the reactions which turn the atoms formed from ablation (of
meteors) and photolysis (of marine gases) into nanometer-sized aerosol
particles. In another collaboration with Mike Cooks synthetic group
measurements are made on the properties of novel phthalocyanines. This
class of molecules has application as photodynamic therapy (PDT) agents;
their capacity to self-assemble on surfaces also makes them potential
candidates for sensor applications.
Chao’s research interest is in investigating nanostructured systems,
from their basic physical and chemical mechanisms of synthesis, through
their optical and electronic properties, to biological and medical applications.
and characterization of Si quantum dots (Si-QDs): Si-QDs prepared by
electrochemical etching and coated with alkyl chains, characterized
by means of AFM, STM, TEM, SAXS, and XPS, Raman spectroscopy, FTIR,
UV/Vis / photoluminescence spectroscopy.
- Evaporation and deposition
of Si-QDs in ultra-high-vacuum (UHV) at relatively low temperatures:
intact sublimation is enabled by a combination of anomalously weak inter-particle
interactions with the extremely high thermal stability of the alkyl-coated
- Biological and medical
applications: size-selected Si-QDs can act as both luminescence probes
(for spatial localisation) and Raman probes (to provide time-resolved
biochemical information) inside living cells. With the observation of
different signals between cancer cells and normal cells, this method
could have potential application in diagnosis.
- Applications in memory
devices: Silicon quantum dot memories, in which the SiO2 layer is replaced
by a Si-QD monolayer, have attracted considerable attention in the last
few years as one of the simplest evolutions of the standard flash technology,
allowing for improved reliability and scaling perspectives.
Clayden’s interests lie in the structure and dynamics of chemical
systems, ranging from zirconium phosphonate supports to the FMuF state.
The unifying theme of his research is the use of magnetic resonance spectroscopy
and relaxation. Two current projects exemplify this:
and dynamics in zirconium phosphonate supports (in collaboration with
Professor M Bochmann).
Multinuclear 13C, 31P and 1H MAS NMR
are being used to characterise the structure of zirconium phosphonates
with ionic liquids as catalyst supports. Incorporation of Pd is evident
through the changes in the 13C CPMAS NMR spectra.
- Double resonance
rf-μSR of the FMuF state in ionic fluorides.
Radiofrequency techniques in μSR are being explored at ISIS, RAL.
Double resonance, in particular, the combination of rf pulses on the
muon and a nuclear spin has not been examined and its potential in μSR
is unclear. In a recent experiment polarisation transfer was attempted
using matched spin-locking rf fields of the FMuF state in a single crystal
of CaF2 and powdered SrF2. Paradoxically despite
the ubiquitous presence of the FMuF state in inorganic fluorides none
was observed in the current CaF2 sample.
Upali A Jayasooriya
of the current projects of Jayasooriyas research group are:
of muon spectroscopies to investigate the fundamental properties of
the classic nanomaterial, DNA. For example this group has measured the
excess electron conduction in DNA over a large temperature range, 2
to 300 K, recognising one- and two-dimensional conduction and identifying
some of the mechanisms in operation. This is a collaboration with Dr
Julea Butt at UEA.
- The group
is also using radiation from synchrotron radiation facilities such as
the European Synchrotron Radiation Facility in Grenoble, France, to
conduct studies based on Nuclear Inelastic Scattering (NIS), an element-selective
vibrational spectroscopy. Two sets of experiments, one with the prototype
metallocene, ferrocene and another with iron-sulfur clusters that model
such entities in protein structures illustrate the potential of this
This is a collaboration with Professor Chris Pickett and Dr Dave Evans
at the John Innes Centre, Norwich Research Park.
Andrew G Mayes
in Andrew Mayess group focuses on three main areas: embedded holograms
in hydrogels; photo-switching hydrogels for microscale valves, pumps and
actuators; surface engineering via photopolymerisation.
provide a good method for probing the behaviour of hydrogel materials.
Mayess research uses this as a method for developing low-cost
chemical sensors with direct visual readout, also to follow the kinetics
and thermodynamics of hydrogel swelling by a variety of mechanisms.
devices have developed rapidly during the last decade, but there are
still significant problems to be overcome in interfacing the micro-separation
and micro-detection steps with appropriate sample and reagent delivery
technology. Photo-switching hydrogels are being investigated as a possible
method to generate integrated pumps and valves for such applications.
group is developing methods to create polymer patterns on gold and metal
oxide surfaces. Polymerisation initiators are attached to the surfaces
(uniformly or in patterns), and these are used to photo-initiate growth
of polymer chains from the surface. This can be for surface patterning
or to produce a variety of polymer architectures to engineer surface
David C Steytler
Steytlers research interests stem from a fascination with the unique
ability of surfactants to self-assemble, both in solution and at interfaces.
Through this process a rich variety of structures (micelles, microemulsions,
vesicles, and liquid crystals) may be formed, often representative of
those found in nature. Steytlers research group is primarily concerned
with the fundamental understanding of such systems and their application
in chemical separation, synthesis and nanofabrication. A variety of specialised
physical methods are employed including Small-Angle Neutron Scattering
(SANS) for structural characterisation, and high pressure tensiometry.
- The development
of surfactants for application in near-critical CO2 and hydrofluorocarbon
of microemulsions, liquid crystal phases and vesicles to control structure
in constrained polymerisation and materials fabrication.
and transport across the oil-water interface microemulsions and
and applications of frozen dispersions.
- The application
of pressure waves in supercritical fluid recrystallisation.