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Quantum Computation in Qudit Space and Applications in Open Quantum Dynamics
No full textQudit, a multi-level computational unit for quantum computing, provides a larger state space for information processing, and thus can reduce the circuit complexity, simplify the experimental setup. We promote the qudit-based quantum computing by providing an overview that covers a variety of qudit topics ranging from gate universality, circuit building, algorithm design, to physical realization methods. Among all the important qudit algorithms, we perform the first experimental realization of a qudit-based phase estimation algorithm(PEA) on a photonic platform, utilizing the high dimensionality in time and frequency degrees of freedom (DoFs) in a single photon. In our scheme the controlled-unitary gates can be realized in a deterministic fashion, as the control and target registers are now represented by two DoFs in a single photon. Next we improve the PEA by introducing a new statistical and variational approach to the PEA that we called SPEA. The SPEA can determine any unknown eigenstate-eigenphase pair from a given unitary matrix by treating the probabilistic output of an Iterative PEA (IPEA)-like circuit as an eigenstate-eigenphase proximity metric, using this metric to estimate the proximity of the input state and input phase to the nearest eigenstate-eigenphase pair and approaching this pair via a variational process on the input state and phase. The SPEA can search over the entire computational space as well as some specified given range efficiently and thus outperforms the original PEA.The simulation of open quantum dynamics has attracted wide interests recently with a variety of quantum algorithms developed and demonstrated. The second half of the thesis focus on the simulation of the open quantum dynamics which is a useful application for quantum computer based on qudit as well as qubit. We perform the first quantum simulations of the radical pair mechanism(RPM) in the avian compass with a Sz.-Nagy dilation theorem-based quantum algorithm to demonstrate the generality of the quantum algorithm and to open new opportunities for studying the avian compass with quantum computing devices. Next we apply the same quantum algorithm to simulate open quantum dynamics based on the Generalized Quantum Master Equation (GQME). This approach overcomes the limitations of the Lindblad equation by providing a rigorous derivation of the equations of motion for any subset of elements of the reduced density matrix. We validate our quantum algorithm as applied to the spin-boson benchmark model by analyzing the impact of the quantum circuit depth on the accuracy of the results when the subset is limited to the diagonal elements of the reduced density matrix. Our findings demonstrate that our approach yields reliable results on noisy intermediate-scale quantum (NISQ) computers
Boundary and Domain Wall Theories of 2D Generalized Quantum Double Models
No full textThis dissertation consists of two parts. In the first part, we discuss the boundary and domain wall theories of the generalized quantum double lattice realization of the two-dimensional topological orders based on Hopf algebras. The boundary Hamiltonian and domain wall Hamiltonian are constructed by using Hopf algebra pairings and generalized quantum double. The algebraic data behind the gapped boundary and domain wall are comodule algebras and bicomodule algebras, respectively. The topological excitations in the boundary and domain wall are classified by bimodules over these algebras. Finally, via the Hopf tensor network representation of the quantum many-body states, we solve the ground state of the model in the presence of the boundary and domain wall.In the second part, we introduce the weak Hopf algebra extension of symmetry, which arises naturally in anyonic quantum systems, and we establish weak Hopf symmetry breaking theory based on the fusion closed set of anyons. We present a thorough investigation of the quantum double model based on weak Hopf algebras, including the topological excitations and ribbon operators, and show that the vacuum sector of the model has weak Hopf symmetry. The gapped boundary and domain wall theories are also established. We show that the gapped boundary is algebraically determined by a comodule algebra, or equivalently, a module algebra, and the gapped domain wall is determined by the bicomodule algebra, or equivalently, a bimodule algebra. We also introduce the weak Hopf tensor network states, by which we solve the weak Hopf quantum double models on closed and open surfaces. Lastly, we discuss the duality of the quantum double phases
Optical Properties of Rydberg Excitons in Cuprous Oxide
No full textCuprous oxide (Cu2O) has recently been proposed as a promising solid-state host for excitonic Rydberg states with large principal quantum numbers (n) whose exaggerated wavefunction sizes (∝ n2) facilitate gigantic, resonant dipole-dipole (∝ n4) and van der Waals (∝ n11) interactions, making them an ideal basis for solid-state Rydberg physics and quantum technology. Synthetic, thin-film Cu2O samples are of particular interest because they can be made defect-free via carefully controlled fabrication and are, in principle, suitable for the observation of extreme single-photon nonlinearities caused by Rydberg blockade. In this work, we present the development of a spectroscopy experiment for characterizing the behavior of Rydberg excitons and use it to study a synthetic thin film of Cu2O grown on a transparent substrate. We present evidence for the presence of states up to n = 8 and conduct the first temperature-dependent study of Rydberg excitons in a thin film. We also propose a technique for studying Rydberg-Rydberg interactions via the creation of high exciton densities and establish a set of rate equations for modeling the processes by which excitons are created, interact with each other, and decay. Finally, we conclude with a discussion of the project’s outlook, as well as what future work will be undertaken to study the interactions between Rydberg excitons and utilize them in scalable, integrable, Rydberg-based quantum devices
Environment Knowledge-Driven Generic Models to Detect Coughs From Audio Recordings
Get PDFGoal: Millions of people are dying due to res- piratory diseases, such as COVID-19 and asthma, which are often characterized by some common symptoms, including coughing. Therefore, objective reporting of cough symp- toms utilizing environment-adaptive machine-learning models with microphone sensing can directly contribute to respiratory disease diagnosis and patient care. Methods: In this work, we present three generic modeling approaches – unguided, semi-guided, and guided approaches consid- ering three potential scenarios, i.e., when a user has no prior knowledge, some knowledge, and detailed knowledge about the environments, respectively. Results: From detailed analysis with three datasets, we find that guided models are up to 28% more accurate than the unguided models. We find reasonable performance when assessing the applicability of our models using three additional datasets, including two open-sourced cough datasets. Con- clusions: Though guided models outperform other models, they require a better understanding of the environment
The Future of Indiana’s Water Resources: A Report from the Indiana Climate Change Impacts Assessment
Get PDFThis report from the Indiana Climate Change Impacts Assessment (IN CCIA) applies climate change projections for the state to explore how continued changes in Indiana’s climate are going to affect all aspects of water resources, including soil water, evaporation, runoff, snow cover, streamflow, drought, and flooding. As local temperatures continue to rise and rainfall patterns shift, managing the multiple water needs of communities, natural systems, recreation, industry, and agriculture will become increasingly difficult. Ensuring that enough water is available in the right places and at the right times will require awareness of Indiana’s changing water resources and planning at regional and state levels
INNOVATION AND HOTEL MANAGEMENT: PROPOSITION OF A HOTEL MANAGEMENT MODEL OF ORGANIZATIONAL INNOVATION FOR VALUE CREATION
No full textPurpose: In line with the effect of international competition and the maturing of customer demands, hotels face the challenges of managing their resources and remaining competitive. Therefore, reevaluating their management models, assessing their ability to innovate and consequently generate value, and maintaining their sustainable performance in the long term is vital. This paper in fact focused on organizational innovation, therefore, the objective of this research was to propose a Hotel Management Model of Organizational Innovation for Value Creation. Design / methodology: The research is exploratory-descriptive, with a quantitative approach and procedures. A pilot study was conducted with 150 American hotel managers, while the final sample included 453 hotel managers in Europe, Asia, North and South America. Findings: The model was validated using Structural Equation Modeling techniques, and it was possible to support 8 of the 14 secondary hypotheses that support the research. Originality / value: In the end, it was possible to realize the importance of a management that encourages the generation of ideas, promoting work practices aligned with human resources, increasing motivation and the development of innovative behavior in individuals. This relationship between leadership and employees fosters the development of the organization\u27s intellectual capital, leveraging the hotel\u27s capacity for innovation and value creation
MEASUREMENT MODEL OF THE PROJECTED AND PERCEIVED IMAGE THROUGH THE ORGANIZATIONAL IDENTITY OF THE VOLVO OCEAN RACE STOPOVER ITAJAÍ BRAZIL SPORT EVENT
No full textPurpose: The success of a tourism product depends on the way it is positioned by its identity, whose reflection is translated into the perceived image, thus demanding the use of strategies that contribute to transmitting a good image. Studies on image emphasize the importance of knowing the perceived image, as well as the image projected through communication channels. In this context, the objective of the research was to propose a model for measuring the Projected and Perceived Image through the Organizational Identity of the Volvo Ocean Race Stopover Itajaí, Brazil. Design / methodology: The study universe includes members of the organizing committee and stakeholders with documentary analysis of the event\u27s media and digital social networks. In-depth interviews were conducted using Collective Subject Discourse for data interpretation. Documentary analysis was by means of Deductive Content Analysis and Correspondence Analysis. Findings: The results supported the 3 secondary hypotheses of the research, leading to confirm the central hypothesis that the Constructed Organizational Identity, projected by the image, is perceived by visitors to the Event studied. Originality / value: It is understood as fundamental the expansion of studies regarding Identity and the possibility of its application in tourist events, as social representations, as support also to communication strategies and marketing
Opaque products: an application in the air transport industry
No full textIn the case of non-storable goods and uncertain or changing demand, companies may be focused on introducing pricing practices, such as opaque products. This article provides a theoretical model in order to analyze the optimality of this new pricing practice which aims to generate additional demand. We provide an application of opaque products in the air transport industry due to the nature of the goods and the market conditions of low or uncertain demand that frequently faces and that has recently increased due to the Covid-19 pandemic. Opaque selling may help companies in dealing with excess capacity and generating extra revenues. We focus on how consumers’ risk attitude influences the optimality of opaque products. Moreover, we demonstrate that only if consumers are risk-averse, companies may apply an additional discount over the initial price of the opaque product. Otherwise, opaque selling is always optimal for dealing with excess capacity. However, we demonstrate, under different market conditions, the optimality of opaque selling with the mentioned discount.
Opaque products, uncertainty, pricing, capacity managemen
Markov Models for predicting the Internet of Behaviour (IoB) of tourists: Optical Camera Communications (OCC) as a localization tool for indoor touristic scenarios
No full textThis work proposes a simulation tool of a system aimed to predict the movements of tourists in an indoor scenario. It is based on a visible light positioning (VLP) system using LED lamps and an App in the user\u27s mobile phone. VLP offers a dual illumination-location solution and provides highly accurate indoor positioning data of the user, able to feed Big Data analysis routines based on the Internet-of-behaviour paradigm through Markov models. The development of this tool is the first step to confirm the suitability of Markov models on behaviour predicting using VLP, with particular emphasis on the tourism and leisure industries. This work will open new research guidelines on these environments, significantly to ease the decision-making process in hospitality facilities In the final paper, results obtained through an experimental mock-up system will be presented to validate the proposed prediction model