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Senast publicerade

XY crosstalk in a 25-qubit flip-chip superconducting quantum processor
(2026) Trinh, Hong Quan
Superconducting circuits are among the most promising physical platforms for building a quantum computer. Scaling superconducting quantum processors to thousands and eventually millions of qubits requires not only high-fidelity quantum gates but also the ability to calibrate and execute them simultaneously. XY crosstalk, resulting from electromagnetic coupling between neighbouring qubits and control lines, is one of the main obstacles to this goal, as it introduces coherent errors and leakage that degrade gate performance during parallel operations. While several crosstalk characterisation and mitigation methods have been demonstrated in superconducting quantum processors, a systematic and scalable approach for integrating them into an automated calibration workflow remains a practical challenge, especially for fixed-frequency architectures, where qubit frequencies cannot be tuned away from one another. In this thesis, an experimental protocol has been developed to measure and compensate XY crosstalk at the signal level in Chalmers’ 25-qubit flip-chip fixed-frequency transmon quantum processor. It is shown that the amplitude and phase of the complex XY crosstalk coefficient can be extracted separately for both f01 −f01 and f01 −f12 crosstalk, and that these coefficients can be used for effective active compensation to improve simultaneous gate performance. Specifically, randomised benchmarking shows that by applying the crosstalk compensation scheme, the average single-qubit gate error during simultaneous measurements can be reduced to the same level as the value obtained from isolated operations. The same improvement in leakage rate is also observed for qubit pairs affected by f01 − f12 crosstalk. These results prove that crosstalk-induced coherent errors and leakage errors can be completely removed using calibration and control strategies and represent a step towards reliable parallel operations in large-scale quantum processors.
Integration of Quality and Sustainability in Supply Chain Operations
(2026) Shirinkar, Maziar; Han, Ruiyang
Organizations are increasingly expected to improve both operational performance and sustainability across their supply chains. While Quality Management (QM) and Sustainable Supply Chain Management (SSCM) share several common principles, limited research has explored how they are integrated in practice. This study inves- tigates how organizations integrate sustainability into Quality Management Systems (QMS), the challenges and trade-offs involved, and how different operational con texts influence this integration. A qualitative multiple-case study was conducted in three companies from the hygiene, telecommunications, and construction indus- tries using semi-structured interviews and company documents. The study fur ther demonstrates that the implementation of these mechanisms varies according to product characteristics, supply chain context, and Product Time-Value Sensitivity (MVT). The findings contribute to the literature by providing empirical evidence of how quality management supports sustainability in supply chain operations and by extending the application of the MVT framework to explain differences in sus- tainability integration across industries. The study also offers practical insights for organizations seeking to strengthen sustainability through existing quality manage- ment capabilities.
Reducing Lead Times in Product Development Projects
(2026) Ahlberg, Erik; Rydberg, Jakob
This study is a qualitative case study using an abductive logic investigating the potential for lead time reductions in product development projects within the case company, a large established European automotive manufacturer, specifically from the perspective of their project management office (PMO). To begin, an initial explorative phase took place with the aim of narrowing down the scope and defining subsequent research questions (RQ). The resulting RQs centered on: First, identifying lead time related issues at the company; second, to apply best practice from relevant literature to each issue and propose corresponding possible actions; and finally, curate the possible actions based on feasibility and potential to reduce lead times. To find the lead time related issues, 19 semi-structured interviews were conducted. The interviewees ranged across several functions and hierarchical levels. After the interviews, the answers were analyzed with thematic analysis, and the following main issues were specified: Coordination; Teams and organizational structure; Internal supplier; Pre-development; Testing and prototyping; and Software. Specifically, the first two main issues pointed towards a need to increase cross-functional integration at the operational level, as was found in the literature study, which took place in parallel to the above-mentioned activities as aligned with the abductive logic. The issues of the internal supplier were also seen as benefitting from cross-functional integration. For pre-development, more focused and well-defined scopes in combination with more thorough early phase work was suggested. Likewise, more early phase testing and adopting a modularization strategy was deemed favorable. Concerning, testing and problem-solving itself, less reliance on full system tests and more small-scale tests on the sub-system and component level was found promising. Modularization also showed potential here. Finally, the main software related issues seemingly fit into the pre-development and testing issues and their corresponding solutions. Conclusively, the more detailed proposed actions had already been curated throughout the discussion and also showed a noticeable degree of interconnectedness, hence all proposed actions were recommended, albeit with varying degrees of promise.
Understanding Performance Variation at a Goods Reception
(2026) Larsson, Alex; Nilsson, Isak
This study aims to investigate what factors that affect performance variation at a goods reception through the application of Six Sigma‘s DMAIC methodology. The study adopts a comparative case study design where the main site has been compared to a benchmarked site, operating under largely the same conditions. This has been done by conducting a gemba walk to gain a better understanding of what quantitative data then needed to be collected. The quantitative data consisted of the case company’s own data. The data was then summarized and visualized using exploratory data analysis (EDA) tools, to gain a comprehensive understanding of what differed between the two sites. To explain the findings from the quantitative data, qualitative data was collected through semi structured interviews. From triangulating the quantitative and qualitative data, several root causes to why the main site performed worse than the benchmarked site were identified. Based on identified root causes the study proposes several improvement initiatives, with the purpose of contributing to a better and mitigated performance variation. To ensure successful implementation, the study adopted a change management methodology, where the chosen tool is the Kotter's 8-step change model.
Influence of Early Architectural Decisions on Modular Platform Development
(2026) Jönsson, Anna; Loman, Josef
Platform-based product development is a central strategy for dealing with complexity, en- abling reuse and supporting product variation within large-scale organizations, especially within original equipment manufacturing (OEM). Architectural decisions within early phases are, however, greatly affected by high uncertainty, leading to challenges within the organization. This thesis examines one organization in particular, researching ways of working and conditions needed to navigate uncertainty and improving decision-making during early phases of modular platform development. Distinctive for the study is a qualitative and iterative research where a literature study is combined with empirical data gathered from employees within the organization. The data gathered consist of contextual observations, a survey based on 25 respondents, as well as twelve expert interviews with selected employees within the organization. The empirical results show a lack of common definitions considering core concepts such as "architecture" and "platform," creating semantic noise and misunderstanding between departments. Furthermore, path dependency is identified where the first project tends to unintentionally dictate the long-term rules and limit the platform’s future flexibility. This is amplified by unclear decision mandates, a lack of "platform-first thinking," as well as short-term goals. To deal with these challenges, the thesis proposes a framework supporting decision-making in early phases structured around five key areas: (1) establishing a common language, (2) ensuring requirements-based definitions of common solutions, (3) conducting platform impact assessments, (4) clarifying cross-functional decision mandate and ownership, as well as (5) enforcing the traceability of decision rationales. The framework is designed as a flexible checklist giving the organization a structured method for dealing with uncertainty in early phases, supporting conscious decisions, while not compromising the platform’s long-term flexibility.