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This thesis presents two novel absolute distance measurement techniques which expand the recently developed dynamic frequency scanning interferometry method [1][2][3]. Preliminary work to improve the frequency referencing of the techniques will also be reported. The first method was developed to eliminate gaps in the distance measurement which were present in previous approaches and is referred to as continuous frequency scanning interferometry (continuous FSI). This technique has been successfully demonstrated on stationary targets at a range of 2.5-5 m and moving targets at speeds around 2 mm/s and 8 mm/s. The second method is referred to as enhanced continuous FSI (enhanced CFSI). It addresses one of the main limitations of the continuous FSI technique by greatly increasing the allowable target motion speed. Proof of principle measurements of enhanced continuous FSI have been performed at speeds of up to 16 mm/s and are presented here. The improved frequency referencing technique uses an optical nanofibre to perform saturated absorption spectroscopy of acetylene-13. The equipment, experimental procedure and preliminary results are presented.

Storage ring based synchrotron light sources deliver high brightness radiation generated by high quality electron beam. The electron beam emittance plays an importance role in controlling the brightness and coherence of the radiation output. An extensive design effort is required to optimse the lattice to improve the beam emittance and machine performance. This thesis reports a series of investigations into lattice tuning, modification and full upgrade to improve the machine performance of third generation light sources, using the Diamond storage ring lattice as a model. In the first part of this thesis, the optics functions of the existing lattice are optimised in order to reduce the natural beam emittance. A reduction of 27% is achieved and verified experimentally, although the effects of strong insertion devices (IDs) reduce this improvement. A second study was carried out with the aim of replacing one of the existing double bend achromat (DBA)cell with one and two double-double bend achromat (DDBA) cells providing additional straight sections for IDs. It was proven that the addition of one DDBA cell can be implemented without significant deterioration of the performance of the machine. The case with two DDBA cells however provides a beam lifetime which is only half of the value in the existing machine. A third study was carried out to consider a full lattice upgrade using multibend achromat (MBA) cells aiming for ultra-low emittance. The last part of this thesis concentrates on the study of an improved beam injection scheme employing a pulsed multipole kicker (PM). The aim is to achieve an eficient beam injection while producing a lower perturbation to the stored beam during the injection. Based on particle tracking, the beam injection performance of the scheme is optimised for the existing Diamond and for the one DDBA lattice. The effects of the PM on the stored beam is proven to be negligible. The compatibility of the existing injection system with the new injection scheme is evaluated. Such scheme provides a feasible alternative to the existing injection scheme that could reduce the perturbation during the beam injection during Top-up injection.

The design and construction of a high intensity, thermal energy molecular beam apparatus is described. The system has been used to investigate the spatial distribution of molecules scattered from stainless steel targets with a range of surface finishes. The results indicate marked deviations from cosine scattering, which can be related to the surface finish of the target. The consequences of these results are discussed. Methods of theoretically predicting the spatial distribution of molecules scattered from rough surfaces are reviewed. The performance of the accumulation type of detector used for the majority of the scattering experiments is assessed, with particular reference to the gain and directional properties. The effects of detector misalignment of the experimental detector have been computed and the results are presented. A new type of high sensitivity flow-through molecular beam detector is described. Two versions of the detector have been developed; one for time-of-flight studies where good time resolution is essential, the other for applications where the highest ionisation efficiency is required. It is considered that these detectors will have a wide application in the field of molecular beam detection.

A study has been made of the principles involved in displacement measurement using optical methods, with particular emphasis on intensity - modulated laser beam techniques. Some of the compromises in performance possible in differing situations are discussed. Previous research has dealt with an approach using coherent optical interference. The two methods are compared theoretically, and it is shown that certain advantages are possessed by the Modulated Beam technique. An important component in the system discussed is the Intensity Modulator. Methods of electro-optic modulation have been studied, and a modulator using Lithium Niobate has been designed and built. It requires low modulation voltages, operates in the v. h. f. region, and has the important advantage over similar modulators in that it is completely insensitive to temperature. A theoretical analysis has been carried out on the design of a modulated optical carrier system, which includes a novel approach to the measurement of displacement and distance. Experimental measurements and results from a practical system, using an external target at 60 metres range, are described and shown to compare satisfactorily with theoretical predictions.

The potential usefulness of stopping negative pion beams in radiotherapy is discussed, with particular reference to their physical properties. A brief history of work in this field is given. A low momentum secondary beam line was constructed to transport pions, produced in a target bombarded with 8 GeV/c protons, to an irradiation area. This facility was primarily intended for radiobiological experiments and physical measurements relevant to pion radiotherapy. The stages of the design of the beam line are outlined and details of performance are given. Radiobiological experiments carried out in the peak, plateau and surface regions are summarised. The biological and physical consequences of the beam's wide momentum bite (13% fwhm) are examined. A detailed description is given of an experiment which measured the relative spectra of secondary particles leaving a carbon surface at the pion stopping peak. Si/Csl counter telescopes measured the relative spectra of protons, deuterons, tritons, He ions and Li ions. An unfolding technique was used to derive the pion capture emission spectra, which are compared with published calculations and experimental data. Suggestions are made for an extended programme of secondary particle measurements.

Atom interferometry is a highly versatile experimental technique for precision measurement, with applications in inertial sensing and tests of fundamental physics. Such interferometers rely on high fidelity transfer of atoms between internal states, which can be challenging when working with thermal atom clouds, where a range of resonance frequencies exists. Inhomogeneities in the spatial intensity distribution of the manipulation lasers can also give rise to a range of coupling strengths; both of these effects serve to reduce the fidelity of coherent manipulation operations. Composite pulses offer one route to high fidelity coherent manipulations. In this thesis we investigate the performance of composite pulses in a thermal cloud of Rubidium 85. We find remarkable agreement between theory and experimental investigation of composite inversion pulses, and build on this to model the performance of such pulses in atom interferometers. We also find excellent agreement between our model and the first experimental demonstration of an application of interferometry in the cooling of atoms; this is the first step towards implementing this cooling method in complex structures like molecules.

Visualisation of nano structure is essential for rapidly evolving fields such as lithography, and to gain a greater understanding of mechanisms behind biological processes. This thesis focuses on using coherent diffraction imaging methods to resolve fine biological structures using a high harmonic generation source and a synchrotron source. The majority of work is focused on developing imaging using the ptychography technique using extreme ultraviolet radiation (EUV) at the University of Southampton. The state of the high harmonic generation imaging beam line is first improved. Flux, stability, and coherence have all been improved in order to meet the required beam characteristics for ptychography imaging. We present published experimental data that shows the first high resolution transmission polychromatic ptychography result from a high harmonic source. To the best of our knowledge we also show the first near field ptychography reconstruction on a high harmonic source. The very first images of real biological samples (chromosomes and hippocampal neurons) using high harmonic generation ptychography are presented. We can achieve 54nm resolution over 100 μm field of view of weakly scattering samples imaging both phase and amplitude. Our EUV microscope is compared to data collected using an established hard X-ray synchrotron source, where it is found far more information can be extracted from the inexpensive table-top source at the University of Southampton.