Thibaut Devolder, C2N
Spin-waves (SW), or their quantized counterparts (magnons) are propagating waves formed by the collective spin excitations in a magnetic body. In standard magnetic thin films and devices, the relevant spin-waves have typically frequencies in the 1-50 GHz range and usable wavelengths from 50 nm to 10 µm. As spin-waves determine to a large extent the rate at which one can manipulate the magnetization, they are of central importance in various applications of spin electronics, e.g. solid state magnetic memories, microwave magnetic oscillators and magnetization-based rf devices.
In this seminar, I will start with a survey of inductive methods for the study spin-wave dynamics from their thermal population level to the onset of the non-linear regime. I will focus on the generation, detection, and propagation of spin-waves with three attentions: (i) the impact of SW non-reciprocity, (ii) of the helicity mismatch between SW and electromagnetic radiation, and (iii) the importance of the multimode character of spin wave conduits. I will finally detail how we have harnessed this understanding to fabricate a micrometer-scale spin wave majority gate with frequency multiplexing capability.
Acknowledgment: this work involved collaborations with IMEC Belgium, IPCMS, Strasbourg and CEA Saclay.