PUB - Publikationen an der Universität Bielefeld

Information technology is one of the biggest and most rising industries in the world. This leads to an enormous increase of data we have to store. For this reason we need huge data centers with lots of servers with more and more advanced data storage technology. Our requirements for sophisticated data storage include high density of information per space unit, low access times and preferably low need of energy. However, the largest portion of energy needed in a data center is used for cooling. The gigantic production of wasted heat is one of the biggest issues in data processing. Information technology, for instance, is dominated by semiconductor electronics. The electron is the dominant information carrier and with it its charge. Electron collisions produce heat. This calls for a new method of information transport and for a meaningful use of wasted heat to reduce further energy consumption. The first stage for that was set by spintronics. In spintronics the spin, i.e., the angular momentum of the electron, a property to be understood in terms of quantum mechanics is used. The spin is connected with a magnetic moment and can be manipulated by magnetic fields. Research of materials for applications and devices which use the spin is rising at the same rate as information technology. A logical step is to combine the utilization of the spin in information technology with manipulation by heat. This combination is now known as the branch of spincaloritronics. What this thesis is about focuses on one of the key effects promoting this branch of research, i.e., the Spin Seebeck Effect. It provides a detailed investigation of this effect and all related transport phenomena in a broad range of different magnetic materials.