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The study of light-matter interaction in superconducting quantum circuits has seen remarkable progress over the last 20 years. By engineering artificial atoms, novel quantum phenomena have been demonstrated, and old ideas have come into a new light. Beyond their application to basic science, the prospect of implementing large-scale quantum information processing with superconducting circuits has fueled a rapid development of surrounding technologies, with ever-increasing control over their behavior as a result. The field's success stems primarily from the flexible design and strong non-linearity of the artificial atom, whose coherent interaction with both electrical and mechanical degrees of freedom has opened many doors for science.This thesis deals with the interaction between artificial atoms and quantum fields in one-dimensional waveguides. The waveguide represents a one-dimensional environment for the atom, which we use to study the properties of open quantum systems. All quantum systems are, in fact, open, and interactions between the system and its environment lead inevitably to a loss of energy and quantum coherence. A continuous loss of information into the environment is called a Markovian process. The work contained in this thesis indicates that deviations from a Markovian process can be detected in the steady state of driven systems. This could simplify the detection of non-Markovianity in open quantum systems, as no information about the system's transient dynamics would be necessary.Specifically, this thesis considers both electromagnetic fields in microwave transmission lines and acoustic fields in the form of surface acoustic waves (SAWs) traveling on the surface of solids. The recent realization of artificial atoms interacting with acoustic waves has opened up a new research field called quantum acoustics. We have built a model of the interaction between atoms and SAWs that predicts the existence of a new regime where the atom forms its own cavity. Additionally, we have considered synthesizing electromagnetically induced transparency, a quantum optics phenomena in opaque media where the absorption of photons is canceled, in waveguides using multiple closely spaced two-level systems.Some of the work in this thesis represents experimental work done in collaboration. In the first experiment, we studied the routing of acoustic waves at the quantum level. In the other experiment, we demonstrated electromagnetically induced transparency by creating an effective $\\Lambda$ system using a giant artificial atom. This thesis reviews the numerical techniques used to model these experiments.

We explore routing of propagating phonons in analogy with previous experiments on photons. Surface acoustic waves (SAWs) in the microwave regime are scattered by a superconducting transmon qubit. The transmon can be tuned on or off resonance with the incident SAW field using an external magnetic field or the Autler-Townes effect, and thus the reflection and transmission of the SAW field can be controlled in time. We observe 80% extinction in the transmission of the low power continuous signal and a 40 ns rise time of the router. The slow propagation speed of SAWs on solid surfaces allows for in-flight manipulations of the propagating phonons. The ability to route short, 100 ns, pulses enables new functionality, for instance to catch an acoustic phonon between two qubits and then release it in a controlled direction.

The release of generative AI tools such as OpenAI's ChatGPT has sparked interest in their implications for education. While early discourse emphasized concerns about plagiarism and academic integrity, recent studies have begun to explore the potential of these tools to support teaching and learning. This paper presents a case study on the use of ChatGPT in the redesign of a first-year systems development project course for informatics students. The course required the integration of various course materials, making it a suitable context for evaluating generative AI's role in course material development. The aim of the study is to present lessons learned from using ChatGPT in the development of course content. Drawing on our practical experience as course designers and instructors, we outline lessons learned from using ChatGPT in the creation of key course elements, including case descriptions, SQL scripts, and requirements specifications. We found that ChatGPT was effective for generating coherent initial drafts of content, but its outputs often required refinement to ensure pedagogical alignment. Challenges included the generation of misleading or irrelevant non-functional requirements and logically flawed code, despite syntactic correctness. Our findings highlight the importance of prompt engineering, critical review, and maintaining a human-in-the-loop approach. We conclude that while ChatGPT can significantly reduce development time for some tasks, it should be used as a complementary tool. This study contributes practical insights to the growing field of AI- assisted education.

We show that an open quantum system in a non-Markovian environment can reach steady states that it cannot reach in a Markovian environment. As these steady states are unique for the non-Markovian regime, they could offer a simple way of detecting non-Markovianity, as no information about the system's transient dynamics is necessary. In particular, we study a driven two-level system (TLS) in a semi-infinite waveguide. Once the waveguide has been traced out, the TLS sees an environment with a distinct memory time. The memory time enters the equations as a time delay that can be varied to compare a Markovian to a non-Markovian environment. We find that some non-Markovian states show exotic behaviors such as population inversion and steady-state coherence beyond \\(1/\\sqrt{8}\\), neither of which is possible for a driven TLS in the Markovian regime, where the time delay is neglected. Additionally, we show how the coherence of quantum interference is affected by time delays in a driven system by extracting the effective Purcell-modified decay rate of a TLS in front of a mirror.

This article discusses practices, opportunities, and challenges in local e-government project management by means of a case study involving interviews, document studies, and an element of action research, over eight months. The analysis against e-government success factors finds seven \"critical issues\"; political timing, resource allocation, political mandate, distinction between administrative and political responsibilities, coordination of departments, dependence on providers, and use of standards. We found these issues open for local choice, influences of strong individuals and groups, and chance. This is a consequence of the prevailing strategic model for the public sector, New Public Management, which leaves these issues to be filled by negotiations among many actors with different roles, goals, and action space. The general lesson is that there is a need for practical ways of acting strategically to reduce the risk level and increase the ability to implement policy.

This article discusses practices, opportunities, and challenges in local e-government project management by means of a case study involving interviews, document studies, and an element of action research, over eight months. The analysis against e-government success factors finds seven “critical issues”; political timing, resource allocation, political mandate, distinction between administrative and political responsibilities, coordination of departments, dependence on providers, and use of standards. We found these issues open for local choice, influences of strong individuals and groups, and chance. This is a consequence of the prevailing strategic model for the public sector, New Public Management, which leaves these issues to be filled by negotiations among many actors with different roles, goals, and action space. The general lesson is that there is a need for practical ways of acting strategically to reduce the risk level and increase the ability to implement policy.

Artificial atoms coupled to surface acoustic waves (SAWs) have played a crucial role in the recent development of circuit quantum acoustodynamics (cQAD). In this paper, we have investigated the interaction of an artificial atom and SAWs beyond the weak coupling regime, focusing on the role of the interdigital transducer (IDT) that enables the coupling. We find a parameter regime in which the IDT acts as a cavity for the atom, rather than an antenna. In other words, the atom forms its own cavity. Similar to an atom coupled to an explicit cavity, this regime is characterized by vacuum-Rabi splitting, as the atom hybridizes with the phononic vacuum inside the IDT. This hybridization is possible because of the interdigitated coupling, which has a large spatial extension, and the slow propagation speed of SAWs. We work out a criterion for entering this regime from a model based on standard circuit-quantization techniques, taking only material parameters as inputs. Most notably, we find this regime hard to avoid for an atom on top of a strong piezoelectric material, such as LiNbO\\(_3\\). The SAW-coupled atom on top of LiNbO\\(_3\\) can thus be regarded as an atom-cavity-bath system. On weaker piezoelectric materials, the number of IDT electrodes need to be large in order to reach this regime.

The VEDLIoT project aims to develop energy-efficient Deep Learning methodologies for distributed Artificial Intelligence of Things (AIoT) applications. During our project, we propose a holistic approach that focuses on optimizing algorithms while addressing safety and security challenges inherent to AIoT systems. The foundation of this approach lies in a modular and scalable cognitive IoT hardware platform, which leverages microserver technology to enable users to configure the hardware to meet the requirements of a diverse array of applications. Heterogeneous computing is used to boost performance and energy efficiency. In addition, the full spectrum of hardware accelerators is integrated, providing specialized ASICs as well as FPGAs for reconfigurable computing. The project's contributions span across trusted computing, remote attestation, and secure execution environments, with the ultimate goal of facilitating the design and deployment of robust and efficient AIoT systems. The overall architecture is validated on use-cases ranging from Smart Home to Automotive and Industrial IoT appliances. Ten additional use cases are integrated via an open call, broadening the range of application areas.

The absorption of photons in a three-level atom can be controlled and manipulated by applying a coherent drive at one of the atomic transitions. The situation where the absorption is fully canceled, and the atom thus has been turned completely transparent, has been coined electromagnetically induced transparency (EIT). The characteristics of EIT is a narrow transparency window associated with a fluorescence quench at its center frequency, indicating that inelastic scattering at this particular point is suppressed. The emergence of EIT-like transparency windows is common in waveguide quantum electrodynamics (QED) when multiple closely spaced quantum emitters are coupled to a waveguide. The transparency depends on the separation and energy detuning of the atoms. In this work, we study a number of different setups with two-level atoms in waveguide QED that all exhibit EIT-like transparency windows. Unlike the case of a genuine three-level atom, no drive fields are required in the systems we consider, and the coherent coupling of energy levels is mediated by the waveguide. We specifically distinguish between systems with genuine EIT-like dynamics and those that exhibit a transparency window but lack the fluorescence quench. The systems that we consider consist of both small and giant atoms, which can be experimentally realized with artificial atoms coupled to either photons or phonons. These systems can offer a simpler route to many EIT applications since the need for external driving is eliminated.