Coherent superposition of exciton states in quantum dots induced by surface plasmons

We present an experimental demonstration of strong optical coupling between CdSequantum dots of different sizes which is induced by a surface plasmon propagating on a planar silver thin film. Attenuated total reflection measurements demonstrate the hybridization of exciton states, characterized by the observation of two avoided crossings in the energy dispersion measured for the interacting system.

Simulations of the effect of waveguide cross-section on quantum dot – plasmon coupling

Quantum dot - plasmon waveguide systems are of interest for the active control of plasmon propagation, and consequently, the development of active nanophotonic devices such as nano-sized optical transistors. This paper is concerned with how varying aspect ratio of the waveguide crosssection affects the quantum dot - plasmon coupling. We compare a stripe waveguide with an equivalent nanowire, illustrating that both waveguides have a similar coupling strength to a nearby quantum dot for small waveguide cross-section, thereby indicating that stripe lithographic waveguides have strong potential use in quantum dot –plasmon waveguide systems. We also demonstrate that changing the aspect ratio of both stripe and wire waveguides can increase the spontaneous emission rate of the quantum dot into the plasmon mode, by up to a factor of five. The results of this paper will contribute to the optimisation of quantum dot - plasmon waveguide systems and help pave the way for the development of active nanophotonics devices.

Bispectral and trispectral characterization of transition to chaos in the Duffing oscillator

Higher-order spectral (bispectral and trispectral) analyses of numerical solutions of the Duffing equation with a cubic stiffness are used to isolate the coupling between the triads and quartets, respectively, of nonlinearly interacting Fourier components of the system. The Duffing oscillator follows a period-doubling intermittency catastrophic route to chaos. For period-doubled limit cycles, higher-order spectra indicate that both quadratic and cubic nonlinear interactions are important to the dynamics. However, when the Duffing oscillator becomes chaotic, global behavior of the cubic nonlinearity becomes dominant and quadratic nonlinear interactions are weak, while cubic interactions remain strong. As the nonlinearity of the system is increased, the number of excited Fourier components increases, eventually leading to broad-band power spectra for chaos. The corresponding higher-order spectra indicate that although some individual nonlinear interactions weaken as nonlinearity increases, the number of nonlinearly interacting Fourier modes increases. Trispectra indicate that the cubic interactions gradually evolve from encompassing a few quartets of Fourier components for period-1 motion to encompassing many quartets for chaos. For chaos, all the components within the energetic part of the power spectrum are cubically (but not quadratically) coupled to each other.

Cultural chaos : Journalism, News and Power in a Globalised World

With examples drawn from media coverage of the War on Terror, the 2003 invasion of Iraq, Hurricane Katrina and the London underground bombings, Cultural Chaos explores the changing relationship between journalism and power in an increasingly globalised news culture. In this new text, Brian McNair examines the processes of cultural, geographic and political dissolution in the post-Cold War era and the rapid evolution of information and communication technologies. He investigates the impact of these trends on domestic and international journalism and on political processes in democratic and authoritarian societies across the world. Written in a lively and accessible style, Cultural Chaos provides students with an overview of the evolution of the sociology of journalism, a critical review of current thinking within media studies and an argument for a revision and renewal of the paradigms that have dominated the field since the early twentieth century. Separate chapters are devoted to new developments such as the rise of the blogosphere and satellite television news and their impact on journalism more generally. Cultural Chaos will be essential reading for all those interested in the emerging globalised news culture of the twenty-first century.

Chaos or complex systems? Identifying factors influencing the success of international and NESB graduate research students in Engineering and Information Technology Fields

The paper explores the results an on-going research project to identify factors influencing the success of international and non-English speaking background (NESB) gradúate students in the fields of Engineering and IT at three Australian universities: the Queensland University of Technology (QUT), the University of Western Australia (UWA), and Curtin University (CU). While the larger study explores the influence of factors from both sides of the supervision equation (e.g., students and supervisors), this paper focusses primarily on the results of an online survey involving 227 international and/or NESB graduate students in the areas of Engineering and IT at the three universities. The study reveals cross-cultural differences in perceptions of student and supervisor roles, as well as differences in the understanding of the requirements of graduate study within the Australian Higher Education context. We argue that in order to assist international and NESB research students to overcome such culturally embedded challenges, it is important to develop a model which recognizes the complex interactions of factors from both sides of the supervision relationship, in order to understand this cohort‟s unique pedagogical needs and develop intercultural sensitivity within postgraduate research supervision.

How quantum theory is developing the field of information retrieval

This position paper provides an overview of work conducted and an outlook of future directions within the field of Information Retrieval (IR) that aims to develop novel models, methods and frameworks inspired by Quantum Theory (QT).

The uses of satire : unorthodox news, cultural chaos and the interrogation of power

This article focuses on the satirical Australian show The Chaser’s War on Everything, and uses it to critically assess the potential political and social ramifications of what McNair (2006) has called ‘cultural chaos’. Drawing upon and analysing several examples from this particular program, alongside interviews with its production team and qualitative audience research, this article argues that this TV show’s engagement with politicians and political issues, in a way that departs from the conventions of traditional journalism, offers a significant opportunity for the interrogation of power. The program’s use of often bizarre and unexpected comedic confrontation allows it to present a perhaps more authentic image of political agents than is often cultivated in mainstream journalism. This suggests therefore that the shift from homogeneity to heterogeneity in the news media – which McNair (2006) sees as a key feature of cultural chaos – presents a significant challenge to those who wish to retain control over what the public sees and understands about the political world, and is a development which should be viewed in positive terms.

Enlightenment out of chaos : power, politics and The Chaser’s War on Everything

This paper focuses on the satirical Australian television show The Chaser’s War on Everything, and uses it to critically explore the potential ramifications of what McNair (2006) has called ‘cultural chaos’. Through an analysis of several examples from this particular program, alongside interviews with its production team and qualitative audience research, this paper argues that this TV show’s engagement with political issues in a creative, entertaining way that departs from the conventions of traditional journalism, allows it to present a perhaps more authentic image of political agents than is often cultivated in the mainstream news media. This paper therefore provides clear evidence that the shift from homogeneity to heterogeneity in the news media presents a significant challenge to those who wish to heavily control public opinion. It also provides further support for an optimistic re-appraisal of entertainment which emphasises its central (not merely periphery) role in political discourse.

Quantum-like non-separability of concept combinations, emergent associates and abduction

Consider the concept combination ‘pet human’. In word association experiments, human subjects produce the associate ‘slave’ in relation to this combination. The striking aspect of this associate is that it is not produced as an associate of ‘pet’, or ‘human’ in isolation. In other words, the associate ‘slave’ seems to be emergent. Such emergent associations sometimes have a creative character and cognitive science is largely silent about how we produce them. Departing from a dimensional model of human conceptual space, this article will explore concept combinations, and will argue that emergent associations are a result of abductive reasoning within conceptual space, that is, below the symbolic level of cognition. A tensor-based approach is used to model concept combinations allowing such combinations to be formalized as interacting quantum systems. Free association norm data is used to motivate the underlying basis of the conceptual space. It is shown by analogy how some concept combinations may behave like quantum-entangled (non-separable) particles. Two methods of analysis were presented for empirically validating the presence of non-separable concept combinations in human cognition. One method is based on quantum theory and another based on comparing a joint (true theoretic) probability distribution with another distribution based on a separability assumption using a chi-square goodness-of-fit test. Although these methods were inconclusive in relation to an empirical study of bi-ambiguous concept combinations, avenues for further refinement of these methods are identified.

A quantum information retrieval approach to memory

As computers approach the physical limits of information storable in memory, new methods will be needed to further improve information storage and retrieval. We propose a quantum inspired vector based approach, which offers a contextually dependent mapping from the subsymbolic to the symbolic representations of information. If implemented computationally, this approach would provide exceptionally high density of information storage, without the traditionally required physical increase in storage capacity. The approach is inspired by the structure of human memory and incorporates elements of Gardenfors’ Conceptual Space approach and Humphreys et al.’s matrix model of memory.

Non-compositional concepts and quantum tests

Compositionality is a frequently made assumption in linguistics, and yet many human subjects reveal highly non-compositional word associations when confronted with novel concept combinations. This article will show how a non-compositional account of concept combinations can be supplied by modelling them as interacting quantum systems.

The quantum inspired modelling of changing attitudes and self-organising societies

We utilise the well-developed quantum decision models known to the QI community to create a higher order social decision making model. A simple Agent Based Model (ABM) of a society of agents with changing attitudes towards a social issue is presented, where the private attitudes of individuals in the system are represented using a geometric structure inspired by quantum theory. We track the changing attitudes of the members of that society, and their resulting propensities to act, or not, in a given social context. A number of new issues surrounding this "scaling up" of quantum decision theories are discussed, as well as new directions and opportunities.

Chaos and creativity of play : designing emotional engagement in public spaces

How do we create strong urban narratives? How do we create affection for our cities? Play, an essential part of any species' biological existence and development, can often be perceived as chaotic and derogatory to social and spatial order. Play is also often perceived as a creative force which generates social and spatial value. This paper looks at the design approaches to both chaotic and creative perceptions of publics at play in urban space. Commonly, Urban and Architectural Design constitutes reactive management of perceived chaos, which derogatorily effects our sensory and emotional engagement with space. Alternatively, Urban and Architectural Design can appeal to the creativity of play, by encouraging unsolicited novelty that is vital to strong experiential narratives in the city and iterating environments that encourage the emergence of physical, emotional and cultural invention. These perceptions of chaos and creativity affect the design methodology of professional practice. Tested through the exciting vehicle of Parkour as urban narrative, the constraints and opportunities of both approaches are presented.

Coupling of energy from quantum emitters to the plasmonic mode of V groove waveguides: A numerical study

This work is a theoretical investigation into the coupling of a single excited quantum emitter to the plasmon mode of a V groove waveguide. The V groove waveguide consists of a triangular channel milled in gold and the emitter is modeled as a dipole emitter, and could represent a quantum dot, nitrogen vacancy in diamond, or similar. In this work the dependence of coupling efficiency of emitter to plasmon mode is determined for various geometrical parameters of the emitter-waveguide system. Using the finite element method, the effect on coupling efficiency of the emitter position and orientation, groove angle, groove depth, and tip radius, is studied in detail. We demonstrate that all parameters, with the exception of groove depth, have a significant impact on the attainable coupling efficiency. Understanding the effect of various geometrical parameters on the coupling between emitters and the plasmonic mode of the waveguide is essential for the design and optimization of quantum dot–V groove devices.