4 Reports on Experimental Results 4.11 Magnon transistor: One magnon current controls another

An attractive direction in next-generation information processing is the development of systems employing particles or quasi-particles other than electrons ideally with low dissipation as information carriers. One such candidate is the magnon: the quasi-particle associated with the eigen-excitations of magnetic materials known as spin waves. Magnonics, the Þeld of science dealing with magnon-based data operations, encompasses a full spectrum of phenomena used in general wave-based signal processing [1]. The data can be coded into magnon phase or density and processed using wave effects such as interference. This approach has already been realised in spin-wave logic gates performing XNOR and NAND operations [24]. The main drawback of these gates is that the input data was coded in a form of DC electric pulses manipulating magnon phases, while the output signal was carried by the magnons themselves. Obviously, that made it impossible to combine two logic gates without additional magnon-to-voltage converters. More-over, the processing of large amounts of data has to be made on the same magnetic chip exclusively within the magnonic system. This fact stimulated a search for a way to control one magnon by another magnon and for the development of the all-magnon device. In this Report we present an insulator-based magnon transistor. The information is carried an