Open Access Theses

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Access status: Open Access ,
An examination of research into children's development, with discussion of implications for national policy and practices in music education in Australia
(2001-05) Barfoed, Elizabeth Mary.
The purpose of this research project is to examine the body of knowledge concerning children’s development in music from the beginning of life, through the early years and in primary school in order to assess the implications for national policy and education practices in music education in Australia.
Access status: Open Access ,
The protection of music as intellectual property : the historical framework and its effects upon contemporary Australian legislation
(1996) Bunting, Sue.
Music is tiie intellectual property of its creator. It came to be included in the ‘fine arts’ along with painting, sculpture, poetry etc. during the eighteenth and nineteenth centuries.
Access status: Open Access ,
Johann Gottlieb Graun : three symphonies : a performing edition with critical commentary
(1983-11) Platt, Heather.
The purpose of this annotated edition of the Symphonies M9 in C, M34 in D and M100 in F is to make three more of Johann Gottlieb Graun’s works readily accessible to musicologists and performers, and in doing so to make a small contribution to the research currently being undertaken into the pre-Classical symphony. A biography of Graun and a discussion concerning his symphonic style are included so that these works may be viewed in their historical perspective. Graun studied violin with Pisendel and Tartini and was himself ranked among Europe’s leading violinists. He was Frederick the Great’s concertmaster for at least thirty-six years, during which time he was responsible for the discipline of the highly acclaimed Berlin opera orchestra. Graun’s compositional output is dominated by instrumental genres, including at least ninety symphonies. These Italianate symphonies are clearly transitional in style, the structure of the outer movements owing more to the rounded binary movements of the Baroque dance suite than to Classical sonata form, while the phraseology of the subjects and the slower harmonic rate of these same movements look toward the future. The slow movements vary in size from mere transitional passages to full-scale binary or ternary movements. However, all too often the melodic lines are disrupted by complex subdivisions of the beat, sudden dynamic contrasts and rests. Despite the uneven quality of his symphonies, Johann Gottlieb Graun holds an important historical position for two reasons. Firstly, he made a major contribution to the dissemination of the Italian symphony throughout northern Germany in the 1730’s and 17AO’s, and, secondly, he was among the first of the north German composers to write mainly concert symphonies.
Access status: Open Access ,
The professional orchestra in the United States : current problems and solutions for improving its future
(1994-12) Balej, Janet Elizabeth.
Professional orchestras have existed in the United States for over a century and a half and enjoyed especially great popularity in this century.
Access status: Open Access ,
Chopin as composer and pianist : stylistic sources
(1994-11) Crisp, Deborah.
Although he was, and is, regarded as one of the foremost virtuosos of the romantic tradition, Chopin considered himself to be apart from that tradition. In his own time, reviews and other reports of his playing and compositions never fail to mention the uniqueness of his style as pianist and composer. However popular he remains, almost 150 years after his death, it is difficult, if not impossible to grasp the extent of his uniqueness, and its precise nature. This thesis sets out to identify significant influences upon the formation of Chopin's style as pianist and composer, and to demonstrate ways in which these are manifested in his work: The writer seeks to confirm Chopin's own assessment of his position as being set apart from the mainstream tradition in his composition, his teaching, and his playing. First, details of Chopin's musical education are examined: in particular the fact that it was primarily directed towards a career in opera composition. The significance of this education is demonstrated in several aspects of his subsequent career as a pianist composer. First and foremost, the very fact that he was not trained (in the usual sense) as a pianist - that he was never subjected to the repetition of conventional pianistic formulae in the form of scales and exercices - must account to some extent for the very different patterns and textures that he was able to discover on the keyboard. The training he did receive appears to have been very rigorous, and perhaps somewhat conservative. Evident in the compositions is a firm grasp of the principles of counterpoint - a feature of his early training with Eisner. His high regard for the work of J.S. Bach is also apparent in the compositions, and it is suggested that Chopin in many ways adopted an eighteenth century attitude towards the composition of particular genres. This reliance on an older tradition is demonstrated also in Chopin's career as pianist and teacher, both in specific technical details and in his attitudes towards performance. The influence of opera is readily apparent in Chopin's compositions, and in accounts of his playing and teaching. This thesis suggests that this influence is more far-reaching: that Chopin's style as pianist and composer is essentially vocal in its conception, and that this was in marked contrast to other composers of the time, whose aim was to emulate the larger palette of the orchestra. The distinctiveness of Chopin's style has often been attributed largely to his Polish origins. This influence is also examined here, though in less detail. It is the writer's contention that this influence has, in general, overshadowed appreciation of the extent to which Chopin's style is based upon eighteenth century techniques and attitudes.
Access status: Open Access ,
"That prelude" : a study of the rise & fall in popularity of Rachmaninov's Prelude in C sharp minor
(1994-11) Bear, Louise.
In 1892, while still studying at the conservatorium in Moscow, Sergei Rachmaninov composed a short prelude in C sharp minor which was to become a focal point for his future career as a performer and composer.
Access status: Open Access ,
Amplification of 2um squeezed light
(2026) Kwan, Kar Meng
Squeezed states of light enable the reduction of quantum noise in precision interferometric measurements and are routinely employed in gravitational-wave detectors. Future gravitational-wave detector upgrades based on cryogenic silicon optics are expected to operate at longer wavelengths near 1984nm, to take advantage of reduced coating thermal noise and substrate absorption. However, at these wavelengths, the observable squeezing is severely limited by optical loss, in particular the reduced quantum efficiency of available photodiodes. This thesis presents the development and experimental demonstration of a loss-tolerant detection scheme for squeezed states at 1984nm. A phase-sensitive optical parametric amplifier is implemented as a pre-amplifier, amplifying the squeezed quadrature prior to photodetection. A theoretical framework is developed to describe the generation, amplification, and detection of squeezed states in the presence of optical loss and phase noise, introducing the concept of effective detection efficiency for amplified readout. The model predicts that phase-sensitive amplification can mitigate detection loss without significantly degrading the quantum correlations of the squeezed state. Experimentally, a squeezed-light source operating at 1984nm is employed, consisting of second-harmonic generation for pump production and an optical parametric oscillator for squeezed vacuum generation. A phase-controlled optical parametric amplifier is added to the squeezed light output for amplified readout. The individual subsystems are characterized in terms of cavity parameters, escape efficiency, nonlinear gain, and control-loop performance. Amplified squeezing is demonstrated with substantially improved effective detection efficiency compared to conventional homodyne readout, despite the limited photodiode quantum efficiency. The technique also enhances noise clearance above the electronic noise floor, extending the usable measurement bandwidth. These results establish phase-sensitive amplification as a practical strategy for overcoming detection loss at long wavelengths and demonstrate its relevance for next-generation gravitational-wave detectors designed for the 2um regime.
Access status: Open Access ,
The Rückert Lieder of Schumann : an analysis of the musical language
(1990-03) Huddleston, Kylie.
The Lied is a unique artistic form, in that it has as its basis a previously existing work, complete in itself.
Access status: Open Access ,
Vocal intonation : an exposition of Pál Kardos' pedagogy of acoustically pure intonation for a cappella music
(1995-02) Pickering, Judith Christine.
Good intonation is an essential condition of a cappella choral music, yet a systematic understanding of how to achieve it is rare among choral directors and aural trainers.
Access status: Open Access ,
Self-esteem and how it relates to singing teaching : an annotated bibliography
(1999-12) Klemke, Michelle
This research project is comprised of an annotated bibliography on self-esteem and how it relates to singing teaching. It is written as the research requirement of the Graduate Diploma of Music (Pedagogy) in the Canberra School of Music, Institute of the Arts, Australian National University. The aims of this project are: • find and review research on this topic • identify the most relevant literature • analyse the literature on how self-esteem interacts with singing • analyse the literature on the relationship between the technical and nontechnical aspects of singing • suggest future research in this area The research undertaken suggests that there is much evidence to support the premise that a relationship exists between singing and self-esteem. The literature suggests that a singing teaching method which involves maintaining a student’s positive self esteem greatly enhances that student's achievement in both technical and non-technical areas of singing and helps them reach their full musical potential. The annotated bibliography is divided into four sections: singing and singing teaching (adults); singing, music and singing teaching (children); music and psychology; and self-esteem. The project highlights a need for further research in this area and an Appendix contains material that may be useful in this regard. This material was unavailable for inclusion in this project.
Access status: Open Access ,
Australia's national song : a catalogue and a chronology
(1981-05) Elias, Anthony.
Australia has taken one hundred and fifty years to acquire a national anthem/song which enjoys even the official recognition which has been accorded Advance Australia Fair. The Australian people have not been unanimous in their choice of the 'most fitting' national anthem for Australia. Attention is drawn to a general ignorance of the nature, and manner of choosing, a national anthem. The histories of various national anthems are traced, showing how they achieved their status. The history of Australia's attempt to find for itself a national anthem is then followed, suggestions being offered as to why most of the various official efforts have failed. There is also a table of contents, a list of plates, a thematic catalogue, an acknowledgements page, a bibliography and an index.
Access status: Open Access ,
Magnetic force microscopy of thin magnetic films
(1993-03) Barnes, Jack Richard.
The development of the Scanning Tunnelling Microscope (STM) in 1982 by Binnig and Rohrer [1] provided the technological leap that spawned several other types of Scanning Probe Microscopes (SPMs), such as the Atomic Force Microscope (AFM) [2] and Scanning Near Field Optical Microscope (SNOM) [3].
Access status: Open Access ,
Using Machine Learning Methods to Estimate Maternal Mortality Ratios
(2025) Rosenberg, Rosalita
Maternal mortality is an ongoing, critical international health challenge, especially in low- and middle-income countries. In 2023, the global maternal mortality ratio (MMR), or the number of maternal deaths per 100,000 live births, was 197. Approximately 95% of maternal deaths occur in low and lower-middle income countries and fragile settings. Many of these deaths could have been prevented by using existing, effective interventions. The World Health Organisation has highlighted how low-quality, sparse data about maternal mortality hinders effective intervention, especially as countries with the highest MMRs tend to have the most missing data. The primary contribution of my thesis to the literature was its development of decision-tree based machine learning models to predict the MMRs of 172 countries between 1985 and 2018 using data from the World Health Organisation and World Bank. In contrast to existing approaches, my proposed models estimated MMR without needing to make explicit assumptions about the underlying distribution of data. My models also used a wider range of socio-economic and health-related features than existing methods. This produced an alternative set of MMR estimates that can be used provide consensus about the true MMR values as well as encourage debate about the validity of different MMR modelling techniques. The best-performing Random Forest Stacking Ensemble achieved a test mean relative error of 0.07 when predicting all MMR data for a specific country and a test mean relative error of 0.37 when forecasting MMR values. Despite being limited by low-quality and sparse input data, my models’ MMR predictions were similar to those produced by the most widely used models in the literature, reinforcing their validity. The socioeconomic and health-related variables with highest predictive power for MMR in my models were established risk factors. My analysis highlighted the importance targeting socio-economic drivers of maternal mortality, such as women’s employment prospects, to successfully reduce maternal deaths.
Access status: Open Access ,
Acoustic communication and collective decision-making in social animal groups
(2026) Liao, Chun-Chieh
Many species live in complex societies in which individuals must coordinate their behaviour to maintain cohesion and gain the benefits of social living, both within and between species. Communication plays a central role in enabling rapid coordination and reducing consensus costs when group members differ in their needs and information. In this PhD thesis, I examine how social animals use communication to coordinate behaviour, particularly in antipredator contexts. The thesis includes introductory and concluding chapters (Chapters 1 and 7), a conceptual review (Chapter 2), and four empirical studies on social birds (Chapters 3-6). In Chapter 2, I develop a conceptual framework describing how acoustic signals and movement cues are used to coordinate behaviour in social animal groups. By integrating information masking, discrimination ability, and encoding limitations, the framework predicts that behaviours involving the timing of events or the expression of specific actions should rely more on acoustic signals, whereas decisions involving complex choices should generally rely on movement cues. This framework also highlights key future directions, including multimodal communication and decision-making in mixed-species groups. Guided by this framework, I conducted three playback experiments on white-winged choughs (Corcorax melanorhamphos), a highly social cooperative breeder. In Chapter 3, I show that adult choughs possess a functionally referential alarm-call system that conveys threat type and urgency. Choughs produce three distinct alarm calls: terrestrial alarms for ground-based predators, aerial whistles for high-flying hawks, and flee alarms for high-urgency threats. Birds responded appropriately to alarm-call playbacks, typically looking around to terrestrial alarms, looking upwards to aerial whistles, and fleeing to flee alarms. In Chapter 4, I show that young choughs develop appropriate alarm-call responses slowly, remaining poor at interpreting alarm calls for several months after fledging. Most juveniles responded to all alarm types by simply looking around, even when exposed to high-urgency flee alarms, suggesting that extended social protection and vocal complexity may shape learning in this species. In Chapter 5, I show that choughs integrate multiple components of social alarm information to coordinate collective antipredator behaviour. They assess alarm-call type to decide what action to take, and caller number to modulate both the intensity of their response and the likelihood of propagating alarm information to others. This decision rule helps reduce false alarms and unnecessary information cascades that can negatively affect group living. Together, these findings demonstrate how acoustic communication enables white-winged choughs to remain both safe and cohesive. In Chapter 6, I extend these insights beyond single-species societies to mixed-species systems. I conducted playback experiments to examine danger information transfer in mixed-species bird flocks in Taiwan. I find strong asymmetries in predator detection and/or danger communication between leader and follower species, with leader species always initiating mobbing calls. However, mobbing calls from leaders did not elicit stronger antipredator responses than those from followers. I propose that larger conspecific group sizes and kin-selected behaviours may favour the evolution of superior antipredator signalling in leader species, leading to asymmetric information transfer about danger between species. These results further suggest that mutual antipredator benefits are common in mixed flocks, promoting positive interspecific interactions and enhancing flock cohesion. Together, these findings suggest that sociality not only increases animals' reliance on social information, but also favours communication systems that allow information about danger to be encoded, assessed, and shared in ways that support effective antipredator behaviour.
Access status: Open Access ,
Studying blood-based immune biomarkers for cancer and their confounders
(2026) Florencia, Lulu
Background: Cancer is a leading cause of death worldwide, with survival strongly dependent on stage at diagnosis. Current screening approaches for early-stage cancer are largely designed to detect a single cancer type, can be invasive, and often have limited sensitivity and specificity. Blood-based immune biomarkers offer a promising, minimally invasive approach for multi-cancer detection, as tumour development induces measurable systemic alterations in circulating leukocyte composition. However, immune profiles are inherently variable and influenced by biological and environmental factors independent of disease status, including genetic background, sex, age, diet, and exercise. The impact of these confounders on immune-based cancer detection is poorly characterised, representing a gap between preclinical findings and clinical translation. Hypotheses/Aims: The central premise of this study is that circulating leukocyte profiles differ between healthy and cancer-bearing individuals, but that intrinsic and extrinsic variables influence these profiles and reduce their ability to indicate cancer if not appropriately accounted for. We further hypothesise that predictive models matched to the host background detect cancer more reliably than mismatched models. The aims were therefore to evaluate the utility of blood-based immune profiles for multi-cancer detection, to assess how biological variability influences classification performance, and to determine whether matching the model to the host background improves detection. Methods: Three syngeneic murine tumour models were used: CT26 (colorectal), 4T1 (mammary) in female BALB/c mice, and RM1 (prostate) in male C57BL/6 mice. Blood was collected at early and late tumour stages, and immune cells were characterised using high-dimensional spectral flow cytometry. Multivariate analyses (PERMANOVA and PCoA) assessed group differences, and Random Forest classification evaluated cancer detection performance, with SHAP-based feature importance identifying key immune predictors. Biological variability was assessed by comparing immune profiles across healthy populations differing by genetic background, sex, age, exercise, diet, and housing environment, and across tumour-bearing populations varying by age and sex within a consistent BALB/c background. Results: First, late-stage tumours produced distinct, tumour-specific immune signatures reliably detectable from blood, whereas early-stage cancers closely resembled healthy controls, with substantial overlap limiting sensitivity. Second, intrinsic factors, particularly genetic background, produced immune variation exceeding tumour-associated changes in many comparisons. Models trained on mismatched healthy populations showed significantly reduced accuracy, primarily impairing early-stage detection while late-stage disease remained detectable; this was not resolved by increasing training data alone, indicating that biological matching, not sample size, is the primary determinant of performance. Third, classification performance was strongly background-dependent in tumour-bearing populations, with old female BALB/c mice achieving the strongest early-stage detection (92% accuracy, 88% sensitivity), while old male BALB/c mice showed consistently reduced performance. Conclusion: Blood-based immune profiles can detect cancer under biologically matched conditions, but reliability is substantially reduced by biological variability, particularly for early-stage disease. This study establishes a preclinical framework for how biological heterogeneity shapes immune biomarker performance and highlights that reliable multi-cancer detection requires a framework accounting for the biological context of both healthy and tumour-bearing populations. These findings inform the future development and clinical translation of blood-based immune biomarkers for cancer screening.
Access status: Open Access ,
The contribution of contemporary Australian composers to the tenor concert repertoire
(1998-06) Cooper, Carl Gerard.
This sub-thesis presents information on composers, selected works, and the views of well known artists who perform new Australian works for the tenor concert repertoire. The sub-thesis is divided into five chapters. The introduction forms Chapter One. Chapter Two discusses Australian composers and their attitudes to their compositions, including their reasons for composing for the tenor voice in particular. Chapter Three evaluates one of the tenor pieces of each of the four Australian composers selected for study. This evaluation discusses the performance requirements of their pieces, and the technical requirements and specific difficulties of the tenor voice. Chapter Four discusses prominent Australian tenor artists' music education, their experiences in dealing with this repertoire, their relationship with Australian composers, and their future interests in this area. Chapter Five concludes the study and provides a closer examination of the current and future directions of concert works for tenor written by contemporary Australian composers. This sub-thesis attempts to give a considered opinion on the paucity of Australian repertoire available to tenor artists for performance andoffers reasons concerning why this situation has developed. The study concludes that the relationship between composer and performer has been responsible for the collaborative nature of some compositions and their performance. On closer observation, the lack of continued performance of these new works is a cause for concern for Australian composers who have written for the tenor concert repertoire, as well as tenor artists who have performed these compositions.
Access status: Open Access ,
Re-discovery of traditional music in Choong-shin Presbyterian Church, Korea
(2001-06) Kim, Jung-min.
This thesis is a study of Korean church music. It investigates the place and nature of music in the Korean Christian church for seeking links between Christianity and Korean traditional music, and trying to define the Korean church’s musical identity. The introduction of Christianity brought radical changes to Korean culture and society. Music was one of these sweeping changes. Although church music has been debated in relation to seeking Korean musical identity, however, Western music has dominated the use of music in church. This phenomenon continues in the contemporary Korean church. However, changes in this situation are beginning to be evident, as some Korean composers consciously apply aspects of traditional music in their works. In spite of this, the use of traditional music in church has not yet been viewed positively because of the Korean church’s indifference and conservatism. However, church music cannot ignore and suppress musical concepts that separate the people in the congregations from their cultural characteristics and the forces of change in the society. A new conception of music for the Korean church is raised here as an important subject, to be considered with the changing musical identity. This study provides a conceptual foundation upon which the Korean church can build and develop its church music into the future.
Access status: Open Access ,
Artificial Intelligence and Organisational Viability in Early Stage Venture Capital
(2026) Jasper, Michelle
Early-stage venture capital (ESVC) decision-making operates under conditions of persistent uncertainty, partial visibility of work, and long feedback delays between investment decisions and outcomes. While recent attention has focused on the potential of artificial intelligence (AI) to improve investment decision-making, less attention has been given to how AI interacts with the organisational structures through which ESVC decisions are produced and regulated. This thesis addresses that gap by examining ESVC decision-making as a question of organisational viability rather than one of optimisation or individual judgement quality. Its aim is to diagnose how ESVC decision systems are functionally structured, how persistent structural tensions within those systems are managed across historical and contemporary practice, and what these tensions imply when AI alters the informational environment in which organisational regulation occurs. Drawing on organisational cybernetics, and in particular Beer's Viable System Model (VSM), this research adopts a diagnostic, abductive approach to analyse how ESVC decision systems manage complexity over time. The empirical study focuses on a single, bounded regional innovation ecosystem characterised by proximity to research institutions, deep-technology ventures, and dense relational networks among investors, intermediaries, and public agencies. Three analytical lenses structure the empirical work. The first examines a historical baseline through analysis of an anonymised ESVC archival corpus spanning eighteen years. The second examines contemporary practice through semi-structured interviews with ESVC practitioners, ecosystem orchestrators, and technology specialists. The third synthesises these lenses to identify persistent structural tensions and interpret their implications under altered informational conditions, specifically, the introduction of AI. The archival diagnosis shows that all core VSM subsystems were present but unevenly enacted, giving rise to structural tensions across four dimensions: autonomy and representability in operational work, formality and informality in coordination, authority and access in oversight, and discretion and consistency in normative governance. Practitioner accounts confirm that these tensions persist in contemporary practice despite changes in tools and organisational contexts, and that they are managed through informal judgement, trust-based calibration, and situational coordination rather than formal regulatory capacity. AI does not resolve these tensions but reconfigures the informational conditions under which they are managed, through four system-level effects: attenuation of local effort, amplification of interpretive misalignment, redistribution of regulatory pressure across roles and recursive levels and obscuring of tacit conditions under which decisions are produced and legitimised. This diagnostic reframes the regulatory function of features (trust, heuristics and informal judgement) that are commonly framed in the decision-making literature as sources of decision error. This thesis makes several contributions: it reframes ESVC decision-making as a question of organisational viability, positioning judgement, trust, heuristics, and bias as functional responses to structural conditions; it provides the first VSM diagnostic of ESVC decision-making at fund level, combining longitudinal archival and contemporary practitioner data; and it conceptualises AI as a redistributor of informational strain rather than a decision-maker or corrective, contributing a diagnostic lens for analysing how AI alters the conditions under which coordination, oversight and organisational learning occur in complex decision systems characterised by uncertainty and delayed feedback.
Access status: Open Access ,
Identification of novel bacterial immunoregulatory factors via a screen of essential genes encoded in Escherichia coli.
(2026) Kurera, Melan
Lipopolysaccharide (LPS) is a known endotoxin that activates the non-canonical inflammasome. Inflammasomes are innate immune complexes that detect microbial structures and trigger the release of inflammatory cytokines together with pyroptotic cell death. In mice, the non-canonical inflammasome senses cytosolic LPS via caspase-11, while in humans this function is mediated by caspase 4 and caspase 5. Despite extensive study, the precise bacterial and host factors that regulate this pathway remain incompletely understood. To address this, we used a single gene knockout library of the Gram-negative bacterium Escherichia coli to identify microbial determinants of inflammasome activation. Primary bone marrow derived macrophages (BMDMs) were infected with wild type or mutant strains. Our screen revealed that mutants lacking the LPS core oligosaccharide (mutants lacking the LPS biosynthesis enzymes RfaC, RfaE, RfaD, and RfaF) exhibited impaired caspase-1 and gasdermin D cleavage, reduced secretion of IL-1beta and IL-18, and attenuated cell death. Importantly, alternative inflammatory pathways remained intact, indicating a specific defect in inflammasome signalling. Further analysis demonstrated that inflammasome activation was dependent on type I interferon signalling and required guanylate binding proteins (GBPs) encoded on chromosome 3, in particular GBP2 and GBP3 were critical player. My work shows that GBP2 bound to the LPS core oligosaccharide, while GBP3 bound to lipid A motif of LPS. Loss of the core oligosaccharide prevented recruitment of these two GBPs. Other GBPs from chromosome 3 did not bind to LPS and could still recruit to the surface of the bacteria suggesting other putative ligands. In vivo, the LPS core oligosaccharide was shown to be an essential signal driving sepsis induced lethality and inflammation in mice. Overall , these findings reveal a fundamental host pathogen interaction in which intact LPS architecture and GBP mediated recognition are required for non-canonical inflammasome activation during E. coli infection. This work elucidates the interface between interferon signalling and inflammasome activation in the cytosolic sensing of LPS, providing a novel molecular target for therapeutic strategies aimed at mitigating pathological inflammation.
Access status: Open Access ,
Engineering Guided Polaritons and Nonlinear Light-Matter Interactions for On-Chip Photonic and Optoelectronic Devices
(2026) Suriyage, Manuka
Controlling light at the nanoscale underpins the advancement of next-generation photonic and optoelectronic technologies, particularly for on-chip integration, optical communication, and quantum information processing. However, conventional photonic systems are fundamentally limited by diffraction, weak light-matter interactions, and inefficient nonlinear effects at subwavelength scales. Overcoming these challenges requires platforms that enable strong coupling between electromagnetic fields and material excitations. In this context, polaritonic excitations and nonlinear optical processes provide complementary approaches for confining, guiding, and generating light within compact systems. Polaritons, arising from the strong coupling between photons and material excitations such as phonons and excitons, enable electromagnetic fields to be confined and guided well below the diffraction limit, supporting directional energy transport. Nonlinear optical processes enable functions such as frequency conversion and quantum light generation. However, challenges remain in achieving deterministic control over excitation pathways, maintaining long-range and low-loss propagation, and translating these effects into practical photonic architectures. Low-dimensional and anisotropic materials provide a promising route to overcome these limitations. Anisotropic polar dielectric crystals can support hyperbolic dispersion, enabling directional polariton propagation. Van der Waals materials offer strong optical confinement and tunable light-matter interactions, with TMDCs standing out due to their strong excitonic resonances and symmetry-dependent optical behaviour. The first part of the thesis focuses on the linear regime and the control of polariton propagation. In anisotropic materials, hyperbolic polaritons enable highly directional transport while remaining confined below the diffraction limit. A key example is the ghost hyperbolic phonon polariton (g-HP), which propagates with oblique wavefronts and exhibits long-range, ray-like behaviour. To address the challenge of selective excitation, a mode-selective approach based on structural asymmetry is developed, where micro- and nano-antennas act as momentum-selective sources. This enables directional propagation and extended propagation lengths. This approach is extended to atomically thin materials, where exciton polaritons emerge in TMDC monolayers. Despite strong excitonic responses, guiding light in such ultrathin systems is challenging due to weak confinement and environmental sensitivity. These limitations are addressed using a suspended monolayer design, enabling direct observation of guided exciton polaritons. The thesis further introduces an interaction-driven approach to topological polaritons. In contrast to conventional systems with pre-designed topology, the platforms studied here are initially topologically trivial. Non-trivial topological phases emerge from strong light-matter coupling, resulting in band hybridization and inversion, and giving rise to robust, backscattering-immune modes. These phases can be dynamically tuned through external parameters such as strain or electrostatic gating. The second part of the thesis focuses on nonlinear light-matter interactions. A valley-selective nonlinear meta-waveguide platform based on non-centrosymmetric TMDCs is developed, enabling efficient SHG with polarization selectivity and directional coupling into guided modes. Building on this, a metasurface-integrated waveguide platform is developed for quantum photonics, enabling efficient nonlinear interactions within a compact footprint. A counterpropagating excitation scheme enables phase matching, supporting both SHG and SPDC. Overall, this thesis establishes strategies for controlling light-matter interactions across both linear and nonlinear regimes, connecting fundamental studies with the development of practical photonic and optoelectronic systems.

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