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We use scanning gate microscopy to study electron transport through an open, gate-defined resonator in a Ga(Al)As heterostructure. Raster-scanning the voltage-biased metallic tip above the resonator, we observe distinct conductance modulations as a function of the tip position and voltage. Quantum-mechanical simulations reproduce these conductance modulations and reveal their relation to the partial local density of states in the resonator. Our measurements illustrate the current frontier between possibilities and limitations in imaging the local density of states in buried electron systems using scanning gate microscopy., Physical Review Research, 3 (3), ISSN:2643-1564

Graphene has evolved as a platform for quantum transport that can compete with the best and cleanest semiconductor systems. Recently, many interesting local properties of carrier transport in graphene have been investigated by various scanning probe techniques. Here, we report on the observation of distinct electronic jets emanating from a narrow split-gate defined channel in bilayer graphene. We find that these jets, which are visible via their interference patterns, occur predominantly with an angle of 60{\deg} between each other. This observation is related to the specific bandstructure of bilayer graphene, in particular trigonal warping, which leads to a valley-dependent selection of momenta for low-energy conduction channels. This experimental observation of electron jetting has consequences for carrier transport in graphene in general as well as for devices relying on ballistic and valley selective transport.

Due to the growing value of software technology in our every-day life, young professionals and undergraduates need to be well-qualified for Software Engineering (SE) careers. Additionally, its didactic basis is a recent development.

Software process models are important in software projects in order to give the work of a project guidelines or a framework. However, teaching process models in higher education seems to be quite challenging. This has to do with the fact that undergraduates have no experience with projects in which process models are used. The theoretical mediation of process models is initially on a very abstract level. For this reason, we chose to combine two didactic approaches, namely problem-based learning and project work. Various traditional plan-driven process models have been expanded in courses in Software Engineering with agile process models. The Scrum Framework is the focus of consideration of this paper. Three Universities of Applied Sciences which cooperate in the EVELIN project focused on Scrum as a process model and integrated it into their teaching. Since the respective concepts of implementation differ, they should be presented and compared in this article to presents some practice approaches. The goal of this presentation of is a uniform evaluation in order to obtain insights from different perspectives. This comparison can draw conclusions for possible necessary improvements of the respective concepts.

Thin nanomaterials are key constituents of modern quantum technologies and materials research. The identification of specimens of these materials with the properties required for the development of state-of-the-art quantum devices is usually a complex and tedious human task. In this work, we provide a neural-network-driven solution that allows for accurate and efficient scanning, data processing, and sample identification of experimentally relevant two-dimensional materials. We show how to approach the classification of imperfect and imbalanced data sets using an iterative application of multiple noisy neural networks. We embed the trained classifier into a comprehensive solution for end-to-end automatized data processing and sample identification.

To handle heterogeneity within students, to foster needed generic competencies, to motivate them, and to increase their employability, Pair Programming seems to be a suitable didactical method to teach and learn programming. In this context, Pair Programming was used in programming lessons and its effectiveness was evaluated. This paper presents the results of the evaluations in order to derive whether Pair Programming is a suitable method to meet the mentioned challenges in a didactically meaningful way.

Internal differentiation is a didactic answer to the growing heterogeneity of the knowledge-base of students based on the rising permeability in higher education (e.g., different qualifications for access to university). As part of an appropriate didactic setting, learning tasks are an essential component, among many other factors. The use of differentiated learning tasks as a reaction to heterogeneity can make an important contribution to teaching/learning. The competency development of students can thus be promoted efficiently. As this diversity is discoverable considering coding in particular among software engineering students, this paper focuses on a beginners' programming course.

As software becomes more and more important in our everyday life, young people have to get the right qualifi­cations for jobs such as programmers, software architects, and software engineers. Since Software Engineering is a relatively new discipline, its didactical foundation is still in its infancy, which contrasts the growing importance and our rising dependence on technology. As a consequence, the goal is to improve learning by using "positive" conceptions of students as "points of departure" and reduce learning obstacles by facing misconceptions. As a first step in this process, (pre-)conceptions have to be identified. Therefore, the paper covers a specification of Grounded Theory, the way it was created and developed further, a presentation of three variants and relevant points of similarity and difference. Furthermore, the research topic of the upcoming study and reasons why GT seems to be a promising research approach regarding the research goal as well as its operationalisation according to this research topic will be displayed.

To handle heterogeneity within students, to foster needed generic competencies, to motivate them, and to increase their employability, a didactical method to teach and learn programming in non-major degree programs shall be found. Therefore, this paper covers strategies and the theoretical underpinning concerning these four challenges and gives solutions how to cope with them. Finally, Pair Programming is presented as a method that addresses the issues introduced here.

In Software Engineering education didactical foundation is still at its beginnings. In recent years, this topic is put into stronger focus, as Software Engineering becomes more and more important in our everyday life. However, it is hard to teach and learn, because of diverse factors, e.g. the immateriality of the product. Therefore it is significant to improve the learning process on the one hand and to minimise obstacles to learning on the other hand. Other disciplines — with a long historical background in their “Fachdidaktik”1 (e.g., biology or chemistry) — have already dealt with one sort of learning barriers; so-called misconceptions. The hurdle that misconceptions create can and will be explained by the constructivist learning theory. This paper covers a research approach to identify, analyse, filter and cluster misconceptions in Software Engineering.

Language — spoken and written — is the medium for information and knowledge sharing; and it is almost always even a role of every subject in (higher) education. The language therefore plays an important part in teaching and learning. This is further underlined by the fact that "discipline-specific language" — which is "the uses of language in university discipline learning and teaching and in professional life in a particular discipline" [1, p. 1] — can be understood as a link between knowledge and generic/personal/interpersonal competencies; especially communication skills. In this paper a research proposal is outlined to enable an enhanced and conscious approach to the use of language and special terms in Software Engineering in higher education. This is done by a two-piece approach that considers terminology from a linguistic and a didactical point of view. All of this combined is intended to contribute toward the development of a terminology in Software Engineering and, in a wider context, to reach the top goal of this research agenda: To be able to obtain recommendations for action for teaching and learning methods to improve the quality and sustainability of teaching and learning in this discipline.

In the context of the Bologna process the “shift from teaching to learning” is postulated to meet two central goals: To increase the students’ employability and to foster needed competencies.

The development of competencies and also the usage of E-Learning and distance education in higher education are key aspects of the Bologna Process. Through the use of E-Learning, individual learning styles (e.g., different learning conditions, speeds and pathways) and competence orientation can be supported and promoted. The combination of traditional classroom teaching and self-study as well as the use of information and communication technologies promise a better quality of teaching. As a result a variety of projects were launched to develop new teaching and learning arrangements while optimizing existing approaches.

Due to the high complexity and numerous abstract processes in the subject Software Engineering (SWE), both, challenges in teaching and in learning arise. The teaching of Software Engineering is attempted by a new didactic approach to convey a deeper understanding of the complexity and the processes of Software Engineering in the context of the course. The approach complements the classical ex-cathedra lecture with a seminar and a project phase, whereby the direct application of theoretical knowledge is achieved in real-world situations. In addition to the consolidation of factual knowledge, transferable skills, such as presentation, communication and teamwork skills, can be encouraged. The approach focuses on self-studying as well as collaborative learning. The knowledge gained from team working is multiplied by the Wiki and spread over the whole semester.

University education in Software Engineering is a challenge for both lecturers and students. Software Engineering is a very complex theme requiring various technical and nontechnical skills. At the beginning of a research project we asked which competencies our graduates need in their everyday working life.

Software Engineering is a very complex and abstract process and therefore hard to learn and hard to teach. Especially in mechatronics software engineering is not the main focus of the university studies. Therefore students have little understanding and low motivation to spend time on it. In this paper, we share some experiences on how we tried to give students a deeper understanding for software engineering, its processes and the complexity of software engineering projects. To that end, we chose a new didactical approach consisting of direct instruction and activating learning styles in parallel. The classical lectures were supplemented by a seminar and a project phase to allow students to apply their theoretical learned knowledge without delay in realistic settings. We combined active and passive learning styles to give students the opportunity to consolidate factual knowledge, foster soft skills (e.g. presentation and communication skills), improve team work and gain a deeper understanding of software engineering processes. The experiences of our courses in summer semesters 2010 and 2012 lead to a further development of our didactical approach in 2013. As a consequence, we tried further methods to spread needed information across the student working groups by using a wiki-system, a market of knowledge or mixing the groups between seminar and project phase. At the end of the seminar phase quality gates were implemented and also awards at the end of the project phase. Systematically evaluations at the end of the seminar phase and at the end of the project work show the learning outcomes and possible further improvements of our didactical approach.

We use scanning gate microscopy to demonstrate the presence of localized states arising from potential inhomogeneities in a 50nm wide, gate-defined conducting channel in encapsulated bilayer graphene. When imaging the channel conductance under the influence of a local tip-induced potential, we observe ellipses of enhanced conductance as a function of the tip position. These ellipses allow us to infer the location of the localized states and to study their dependence on the displacement field. For large displacement fields, we observe that localized states tend to occur halfway into the channel. All our observations can be well explained within the framework of stochastic Coulomb blockade., Physical Review Research, 2, ISSN:2643-1564