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This dissertation deals with male and female social identities during the Middle Bronze Age (1600-1300 BC) in southern Scandinavia and northern Germany. South Scandinavian Bronze Age research has traditionally focused on the male sphere, while women have seldom been seriously considered or analysed in terms of their roles, power or influences on society. This study addresses the imbalance through discussing the evidence for gender relations, social structures and identity. The topic will be approached using case studies from different areas of northern Europe and from a variety of angles (e.g. costume and appearance, age, violence, long distance contacts), always drawing on the rich material from burials. How people presented themselves varied not only between different areas, but also over time. Groups that treated material culture in a fairly similar way during Period IB (c. 1600-1500 BC) start treating it in different ways during Period II (c. 1500-1300 BC). In southern Scandinavia during Period II the material culture is fairly similar on the whole, but the different geographical groups use the artefacts in different ways. The level of violence seems to have fluctuated in the area during the Middle Bronze Age, with some areas showing more signs of violence at certain times. On the other hand the view on ageing seems to have been fairly similar over a large part of central and northern Europe, and from age 14 one seems to have been regarded as an adult. The dissertation also shows that long distance contacts were important and wide-ranging, and people seem to have moved across large areas of Europe, even if the visible exogamous marriage pattern seems to have decreased in distance from Period IB to Period II. In conclusion, although there seems to have been a general European pattern concerning e.g. the view on age, the archaeological record reveals many local variations in how this was expressed, e.g. on the body.

The goal of the research reported in this thesis is to establish the feasibility of a novel optical architecture for an optical route & select circuit switch suitable for implementation as a photonic integrated circuit. The proposed architecture combines Optical Phased Array (OPA) switch elements implemented as multimode interference coupler based Generalised Mach-Zehnder Interferometers (GMZI) with a planar Lüneburg lens-based optical transpose interconnection network implemented using graded metamaterial waveguide slabs. The proposed switch is transparent to signal format and, in principle, can have zero excess insertion loss and scale to large port counts. These switches will enable the low-energy consumption high capacity communications network infrastructure needed to provide environmentally-friendly broadband access to all. The thesis first explains the importance of switch structures in optical communications networks and the difficulties of scaling to a large number of switch ports. The thesis then introduces the Talbot effect, i.e. the self-imaging of periodic field distributions in free space. It elaborates on a new approach to finding the phase relations between pairs of Talbot image planes at carefully selected positions. The free space Talbot effect is mapped to the waveguide Talbot effect which is fundamental to the operation of multimode interference couplers (MMI). Knowledge of the phase relation between the MMI ports is necessary to achieve correct operation of the GMZI OPA switch elements. An outline of the design procedures is given that can be applied to optimise the performance of MMI couplers and, as a consequence, the GMZI OPA switch elements. The Lüneburg Optical Transpose Interconnection System (LOTIS) is introduced as a potential solution to the problem of excessive insertion loss and cross-talk caused by the large number of crossovers in a switch fabric. Finally, the thesis explains how a Lüneburg lens may be implemented in a graded ‘metamaterial’, i.e. a composite material consisting of ‘atoms’ arranged on a regular lattice suspended in a host by nano-structuring of silicon waveguide slabs using a single etch-step. Furthermore, the propagation of light in graded almost-periodic structures is discussed. Detailed consideration is given to the calibration of the local homogenised effective index; in terms of the local parameters of the metamaterial microstructure in the plane and the corrections necessary to accommodate slab waveguide confinement in the normal to the plane. The concept and designs were verified by FDTD simulation. A 4×4 LOTIS structure showed correct routing of light with a low insertion loss of -0.25 dB and crosstalk of -24.12 dB. An -0.45 dB excess loss for 2D analysis and an -0.83 dB insertion excess loss for 3D analysis of two side by side metamaterial Lüneburg lenses with diameter of 15 μm was measured, which suggests that the metamaterial implementation produces minimal additional impairments to the switch.

The goal of the research reported in this thesis is to establish the feasibility of a novel optical architecture for an optical route & select circuit switch suitable for implementation as a photonic integrated circuit. The proposed architecture combines Optical Phased Array (OPA) switch elements implemented as multimode interference coupler based Generalised Mach-Zehnder Interferometers (GMZI) with a planar Lüneburg lens-based optical transpose interconnection network implemented using graded metamaterial waveguide slabs. The proposed switch is transparent to signal format and, in principle, can have zero excess insertion loss and scale to large port counts. These switches will enable the low-energy consumption high capacity communications network infrastructure needed to provide environmentally-friendly broadband access to all. The thesis first explains the importance of switch structures in optical communications networks and the difficulties of scaling to a large number of switch ports. The thesis then introduces the Talbot effect, i.e. the self-imaging of periodic field distributions in free space. It elaborates on a new approach to finding the phase relations between pairs of Talbot image planes at carefully selected positions. The free space Talbot effect is mapped to the waveguide Talbot effect which is fundamental to the operation of multimode interference couplers (MMI). Knowledge of the phase relation between the MMI ports is necessary to achieve correct operation of the GMZI OPA switch elements. An outline of the design procedures is given that can be applied to optimise the performance of MMI couplers and, as a consequence, the GMZI OPA switch elements. The Lüneburg Optical Transpose Interconnection System (LOTIS) is introduced as a potential solution to the problem of excessive insertion loss and cross-talk caused by the large number of crossovers in a switch fabric. Finally, the thesis explains how a Lüneburg lens may be implemented in a graded ‘metamaterial’, i.e. a composite material consisting of ‘atoms’ arranged on a regular lattice suspended in a host by nano-structuring of silicon waveguide slabs using a single etch-step. Furthermore, the propagation of light in graded almost-periodic structures is discussed. Detailed consideration is given to the calibration of the local homogenised effective index; in terms of the local parameters of the metamaterial microstructure in the plane and the corrections necessary to accommodate slab waveguide confinement in the normal to the plane. The concept and designs were verified by FDTD simulation. A 4×4 LOTIS structure showed correct routing of light with a low insertion loss of -0.25 dB and crosstalk of -24.12 dB. An -0.45 dB excess loss for 2D analysis and an -0.83 dB insertion excess loss for 3D analysis of two side by side metamaterial Lüneburg lenses with diameter of 15 μm was measured, which suggests that the metamaterial implementation produces minimal additional impairments to the switch.

The present dissertation examines constructions of femininity in the lyrical and didactical works of Elisabeth von Braunschweig-Lüneburg (1510-1558). It shows how this widow ruler and promoter of the reformation transforms and re-interprets contemporary ideas about women and gender according to her own personal interests, and how gender roles are thus negotiated in her texts. In accordance with current theoretical ideas about subjectivity, discourse, and gender, it is shown among other things how Elisabeth von Braunschweig-Lüneburg uses established genres to further her own personal agenda, and how she manipulates contemporary notions of gender in order to create authority for herself as a political force, as an upholder of Christian virtues, and, most importantly, as a writer. The analysis is based on an understanding of subjectivity as dialogical – as a negotiation with the surrounding culture – and of gender as socially constructed. Using the theories presented by Judith Butler and Joan Wallach Scott as a basis, the study shows how Elisabeth works within the various discourses available to her in order to describe established gender roles in a fashion that challenges prevailing notions of femininity and a woman’s place in society. The study focuses on a number of aspects of femininity important in Elisabeth’s texts as well as in the cultural context in which they were written. The textual construction of woman as writer, ruler, preacher, wife, mother, and widow is examined. The dissertation presents not previously acknowledged insights into the ambivalence coloring Elisabeth’s descriptions of women and femininity.

The widespread adoption of photonic circuits requires the economics of volume manufacturing offered by integration technology. A Complementary Metal-Oxide Semiconductor compatible silicon material platform is particularly attractive because it leverages the huge investment that has been made in silicon electronics and its high index contrast enables tight confinement of light which decreases component footprint and energy consumption. Nevertheless, there remain challenges to the development of photonic integrated circuits. Although the density of integration is advancing steady and the integration of the principal components – waveguides, optical sources and amplifiers, modulators, and photodetectors – have all been demonstrated, the integration density is low and the device library far from complete. The integration density is low primarily because of the difficulty of confining light in structures small compared to the wavelength which measured in micrometers. The device library is incomplete because of the immaturity of hybridisation on silicon of other materials required by active devices such as III-V semiconductor alloys and ferroelectric oxides and the difficulty of controlling the coupling of light between disparate material platforms. Metamaterials are nanocomposite materials which have optical properties not readily found in Nature that are defined as much by their geometry as their constituent materials. This offers the prospect of the engineering of materials to achieve integrated components with enhanced functionality. Metamaterials are a class of photonic crystals includes subwavelength grating waveguides, which have already provided breakthroughs in component performance yet require a simpler fabrication process compatible with current minimum feature size limitations. The research reported in this PhD thesis advances our understanding of the structure-property relations of key planar light circuit components and the metamaterial engineering of these properties. The analysis and simulation of components featuring structures that are only just subwavelength is complicated and consumes large computer resources especially when a three dimensional analysis of components structured over a scale larger than the wavelength is desired. This obstructs the iterative design-simulate cycle. An abstraction is required that summarises the properties of the metamaterial pertinent to the larger scale while neglecting the microscopic detail. That abstraction is known as homogenisation. It is possible to extend homogenisation from the long-wavelength limit up to the Bragg resonance (band edge). It is found that a metamaterial waveguide is accurately modeled as a continuous medium waveguide provided proper account is taken of the emergent properties of the homogenised metamaterial. A homogenised subwavelength grating waveguide structure behaves as a strongly anisotropic and spatially dispersive material with a c-axis normal to the layers of a one dimensional multi-layer structure (Kronig-Penney) or along the axis of uniformity for a two dimensional photonic crystal in three dimensional structure. Issues with boundary effects in the near Bragg resonance subwavelength are avoided either by ensuring the averaging is over an extensive path parallel to boundary or the sharp boundary is removed by graded structures. A procedure is described that enables the local homogenised index of a graded structure to be determined. These finding are confirmed by simulations and experiments on test circuits composed of Mach-Zehnder interferometers and individual components composed of regular nanostructured waveguide segments with different lengths and widths; and graded adiabatic waveguide tapers. The test chip included Lüneburg micro-lenses, which have application to Fourier optics on a chip. The measured loss of each lens is 0.72 dB. Photonic integrated circuits featuring a network of waveguides, modulators and couplers are important to applications in RF photonics, optical communications and quantum optics. Modal phase error is one of the significant limitations to the scaling of multimode interference coupler port dimension. Multimode interference couplers rely on the Talbot effect and offer the best in-class performance. Anisotropy helps reduce the Talbot length but temporal and spatial dispersion is necessary to control the modal phase error and wavelength dependence of the Talbot length. The Talbot effect in a Kronig-Penny metamaterial is analysed. It is shown that the metamaterial may be engineered to provide a close approximation to the parabolic dispersion relation required by the Talbot effect for perfect imaging. These findings are then applied to the multimode region and access waveguide tapers of a multi-slotted waveguide multimode interference coupler with slots either in the transverse direction or longitudinal direction. A novel polarisation beam splitter exploiting the anisotropy provided by a longitudinally slotted structure is demonstrated by simulation. The thesis describes the design, verification by simulation and layout of a photonic integrated circuit containing metamaterial waveguide test structures. The test and measurement of the fabricated chip and the analysis of the data is described in detail. The experimental results show good agreement with the theory, with the expected errors due to fabrication process limitations. From the Scanning Electron Microscope images and the measurements, it is clear that at the boundary of the minimum feature size limit, the error increases but still the devices can function.

Text in English, with abstracts and keywords in English and Xhosa / The study delves into traumatic memories rooted in the unconscious mind and the modalities of expression of traumatic memories of childhood. Specific reference is made to the trauma studies of Cathy Caruth and Bessel van der Kolk. Using a framework of contemporary trauma theory, I argue that trauma manifests through childhood sexual abuse (CSA) manifests in trauma and that a number of artworks by myself, Penny Siopis and Nathani Lüneberg, reflect such trauma. The research is conducted as practice-led research and focuses on interpretations of selected artworks as well as a theoretical component. The body of large-scale digital paintings plays a significant role in the research process, which implies that theory leads practice and vice versa. The work encompasses the visual exploration of CSA and it is specifically analysed according to my interpretation of symbols such as the naked female body and intimate scenes which illustrate, vulnerabilty, curtains that metaphorically represent a view into my unconscious mind. The symbol of the uterus or the womb, where a foetus or unborn baby develops and grows, is a symbol of nurturing and protection. The artworks are primarily considered according to notions of CSA that cause betrayal and traumatic associations with sex, angst and psychological fragility in children. The exhibition portrays the psychobiological and psyhoanalytical aspects of childhood trauma resulting from CSA. The creative work consists of four digital paintings and seven photographic artworks. The artworks in The Silent Wound Series portray CSA, childhood trauma, and traumatic memories in the unconscious. Dealing with the understanding and representation of childhood trauma such as CSA, these themes are continuously embodied in my artworks. As the portrayal of the fragile girl child’s body as a signifier in the artworks relates to my personal situation, I choose an empathic view of childhood trauma within the study, portraying traumatic events and the memories thereof in the unconscious. The aim of the study is to recognise how digital painting and photography enable the representation and understanding of CSA and traumatic memories and how the silenced and abused child’s voice can be expressed through the affective and transactive quality of art. The main study objective is to investigate if traumatic memories occur in victims of CSA. / Uphononongo lungena nzulu kwiinkumbulo ezoyikisayo ezendele kwingqondo eleleyo kunye neendlela zokubonisa iinkumbulo ezibuhlungu zobuntwana. Ngokukhethekileyo kujoliswe kuphando olwenziwe kwizifundo zomothuko zikaCathy Caruth noBessel van der Kolk. Ndisebenzisa isakhelo sethiyori yanamhlanje, ndivakalisa ukuba umothuko wokuxhatshazwa ngokwesondo ebuntwaneni (i-CSA) bubonakala kuloyiko kwaye eminye yemisebenzi yam yobugcisa, uPenny Siopis kunye noNathani Lüneberg, ibonisa uloyiko olunjalo. Uphando lwenziwa njengophando olukhokelwa kukuziqhelanisa kwaye lujolise kutoliko lwemisebenzi yobugcisa ekhethiweyo kunye nenxalenye yethiyori. Uvimba wemizobo emikhulu yedijithali idlala indima ebalulekileyo kwinkqubo yophando, oko kuthetha ukuba ithiyori ikhokelela ekusebenzeni kwaye nangokuphendulelekileyo. Umsebenzi uquka uphando olubonakalayo kwe-CSA kwaye ucazululwa ngokukodwa ngokokutolika kwam iisimboli ezinje ngomzimba wabasetyhini ehamba ze kunye nemiboniso esondeleleneyo ebonisa, ukuba sesichengeni, iikhethini ngokukwekwayo ezimele imbono kwingqondo yam eleleyo. Uphawu lwesibeleko okanye isibeleko, apho umbungu okanye usana olungekazalwa lukhula khona kwaye lukhule, siluphawu lokondla nokukhusela. Imisebenzi yobugcisa iqwalaselwa ikakhulu ngokwemibono ye-CSA ebangela ukungcatshwa kunye nomanyano oludakumbisayo ngezesondo, ixhala kunye nobu-ethe-ethe ngokwengqondo ebantwaneni. Umboniso uzoba iimeko zengqondo ephilayo kunye nohlalutyo lwengqondo elimeleyo yobuntwana ebangelwe yi-CSA. Umsebenzi wobugcisa unemizobo emine yedijithali kunye neefoto zobugcisa esixhenxe. Imisebenzi yobugcisa kwi-Silent Wound Series izoba i-CSA, umothuko wobuntwana, kunye neenkumbulo ezibuhlungu ezikwingqondo eleleyo. Ukusebenza nokuqonda nokutolika ukwenzakaliswa kobuntwana okufana ne-CSA, le mixholo ihlala iyinxalenye kwimisebenzi yam yobugcisa.Njengoko ukwenza uzobo lomzimba o-ethe-ethe womntwana oyintombazana njengomboniso kwimisebenzi yobugcisa kunxulumene nemeko yam yobuqu, ndikhetha umbono onovelwano wokwenzakala kobuntwana kolu phononongo, ndibonisa iziganeko ezihlasimlis 'umzimba kunye neenkumbulo zazo ezingqondweni ezileleyo. Injongo yophando kukufuna ukuqonda ukuba imizobo ngedijithali kunye nokufota kukwenza njani ukumelwa kunye nokuqondwa kwe-CSA neenkumbulo ezenzakalisayo nokuba ilizwi elithulisiweyo nempatho-mbi yomntwana linokuvakaliswa njani ngokomgangatho ochaphazelayo notshintshayo wobugcisa. Eyona njongo iphambili yophando kukuphanda ukuba iinkumbulo ezibuhlungu ziyenzeka kumaxhoba e-CSA. / Arts and Music / M.V.A.