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This study discusses the pedagogical characteristics of the hands-on nterdisciplinary innovation course Experts in Teams (EiT) of the University of Southern Denmark (SDU).EiT is a 10 ECTS course mandatory to all fifth semester students on any engineering program at the Technical Faculty of SDU. Course duration is 12 weeks with two weekly sessions of which only one is teacher controlled. In 2016 EiT involved approximately 425 students, 22 teaching resources, and 6companies. These numbers will increase in the years to come.Traditionally we distinguish between practical courses and theoretical courses. Most of the practical courses are group work along the lines of project based learning. EiT is in a way both. It is a practical course in as much as our students get hands-on experience with interdisciplinary team work and innovation processes. EiT is a theoretical course in as much as our students are taught various tools that aid and guide them in the innovation process and in the interdisciplinary team work. The theoretical foundations of EiT viewed as a teaching method is experiential learning and its derivative project based learning. In the beginning of the 12 weeks course period EiT is taught much like a traditional theoretical course. After only a few weeks this all changes and the teachers become facilitatorsof the students’ own learning which is relevance-steered by the innovation project at hand. These characteristics are typical for experiential learning and in this way EiT becomes a learning method rather than a teaching method. Besides discussing the pedagogical characteristics of EiT, the study also gives a general introduction to EiT as it was taught at SDU fall 2016 as well as a brief review of the basic theory behind experiential learning. As such this study serves both as an introduction to e.g. new teachers of EiT but also as a starting point for a clarification of the features that makes EiT an experiential learning endeavor.

The focal point of the research presented here is all-optical signal processing via nonlinearities. The objective has been to investigate the interaction between optical signals via nonlinearities and how these nonlinearities can be engineered to serve specific purposes. The nonlinear response of materials with a second order nonlinearity, the so-called X(2) materials, is faster and stronger than that of more conventional materials with a cubic nonlinearity. The X(2) materials support spatial solitons consisting of two coupled components, the fundamental wave (FW) and its second harmonic (SH). During this project the interaction between such spatial solitons has been investigated theoretically through perturbation theory and experimentally via numerical simulations. The outcome of this research isnew theoretical tools for quantitatively predicting the escape angle, i.e. the angle of incidence below which the solitons will fuse and above which they will move apart. Head-on collision experiments are not comprised within the model assumptions, but even so expressions predicting the so-called inwards escape angle are proposed and numerically veriÝed for certain cases. Chapter 2 and paper 1 are dedicated to this part of the research. In chapter 4 the generality of the theoretical approach is emphasised with the derivation and verification of equivalent tools for media with a saturable nonlinearity. The strength of the X(2) nonlinearity strongly depends on the phase mismatch between the FW and the SH. Via quasi-phase-matching (QPM) the phase mismatch and hence the nonlinearity is eÙectively brought under control through periodic sign reversal of the nonlinearity. On theaverage QPM changes the quadratic nonlinearity and induces new cubic nonlinearities in the system. The engineering and exploitation of these cubic nonlinearities in two-period QPM wave-guides has been another area of investigation. Introducing the second period might make practical engineering of the nonlinearities possible. A major result is the discovery that cubic nonlinearities leads to an enhancement of the bandwidth for soliton generation. This part of the research is presented in Chapter 3 and paper 2.

We develop a theory for nonplanar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called χ(2)) bulk media. We predict quantitatively the outwards escape angle, below which the solitons turn around and collide, and above which they continue to move-away from each other. For in-plane interaction, the theory allows prediction of the outcome of a collision through the inwards escape angle, i.e., whether the solitons fuse or cross. We find an analytical expression determining the inwards escape angle using Gaussian approximations for the solitons. The theory is verified numerically.

We develop a theory for non-planar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called chi(2)) bulk media. We predict quantitatively the outwards escape angle, below which the solitons turn around and collide, and above which they continue to move away from each other. For in-plane interaction the theory allows prediction of the outcome of a collision through the inwards escape angle, i.e. whether the solitons fuse or cross. We find an analytical expression determining the inwards escape angle using Gaussian approximations for the solitons. The theory is verified numerically., V1: 4 pages, 4 figures. V2: Accepted for publication in Physical Review E. 5 pages, 4 figures. Fig. 2 changed to be for fixed soliton width and to show soliton power. New simple relations in terms of power and pahse mismatch are included