Resonant generation of propagating second-harmonic spin waves in nano-waveguides

• Published in: Nature communications 2024-02, Vol.15 (1), p.1827-1827, Article 1827
• Main Authors: Nikolaev, K. O., Lake, S. R., Schmidt, G., Demokritov, S. O., Demidov, V. E.
• Format: Article
• Language: English
• Subjects: 140/125; 639/766/119/1001; 639/925/927/1062; Computation; Damping; Energy transfer; Frequency dependence; Humanities and Social Sciences; Insulators; Magnetic fields; Magnons; multidisciplinary; Nonlinear phenomena; Phase matching; Phase velocity; Science; Science (multidisciplinary); Signal processing; Wave propagation; Waveguides; Waves
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-46108-y

Generation of second-harmonic waves is one of the universal nonlinear phenomena that have found numerous technical applications in many modern technologies, in particular, in photonics. This phenomenon also has great potential in the field of magnonics, which considers the use of spin waves in magnetic nanostructures to implement wave-based signal processing and computing. However, due to the strong frequency dependence of the phase velocity of spin waves, resonant phase-matched generation of second-harmonic spin waves has not yet been achieved in practice. Here, we show experimentally that such a process can be realized using a combination of different modes of nano-sized spin-wave waveguides based on low-damping magnetic insulators. We demonstrate that our approach enables efficient spatially-extended energy transfer between interacting waves, which can be controlled by the intensity of the initial wave and the static magnetic field. Spin waves in magnetic nanosystems offer a potential platform for wave-based signal processing and computing, with a variety of advantages compared to optical approaches. Herein, the authors demonstrate resonant phase matched generation of second harmonic spin waves, enabling the generation of short wavelength spin waves that are otherwise difficult to directly excite.