Industry and academia: pursuing a PhD at Fraunhofer, the best of both worlds

Pursuit of an academic career is often co associated with a PhD which also is a qualification for all types of jobs in industry. However, in Germany most PhD programs focus on university-based, basic, and applied research and aim to demonstrate concepts while the transfer to industry and real products is subordinate. This is where Fraunhofer comes in: our natural science and engineering PhD students participate in solving real-world problems for our industrial customers with innovative and scientific approaches while they simultaneously pursue basic research questions with an application relevance for their PhD thesis. As an example, in this paper we present a multiphysics laser diode simulation software (SEMSIS) which was developed within two industrially funded PhD projects at the Fraunhofer Institute for Laser technology ILT. In the fusion research, a vast number of high-power laser diodes are used as pump sources for the high-energy pulsed lasers in inertial confinement fusion. Improving their electro-optical efficiency and making them more robust against external optical feedback represents a crucial step towards their use in economically competitive fusion power plants. In the presented simulation software tool SEMSIS, the complex interaction of electrical, optical, thermal as well as mechanical properties and their impact on efficiency, filamentation and reliability of high-power diode lasers can be analyzed to address the previously mentioned requirements in fusion research.