High-efficiency control of spin-wave propagation in ultra-thin yttrium iron garnet by the spin-orbit torque

• Published in: Applied physics letters Vol. 108; no. 17
• Main Authors: Evelt, M., Demidov, V. E., Bessonov, V., Demokritov, S. O., Prieto, J. L., Muñoz, M., Ben Youssef, J., Naletov, V. V., de Loubens, G., Klein, O., Collet, M., Garcia-Hernandez, K., Bortolotti, P., Cros, V., Anane, A.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 25-04-2016
• Subjects: AMPLIFICATION; Applied physics; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Coherent scattering; CONTROL; DAMPING; FERRITE GARNETS; IRON; LAYERS; Magnetic damping; Magnons; NONLINEAR PROBLEMS; Physics; Propagation; SCATTERING; SPATIAL RESOLUTION; SPIN; SPIN WAVES; Torque; Transmission lines; Wave amplification; WAVE PROPAGATION; WAVEGUIDES; YTTRIUM; Yttrium-iron garnet
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4948252

We study experimentally with submicrometer spatial resolution the propagation of spin waves in microscopic waveguides based on the nanometer-thick yttrium iron garnet and Pt layers. We demonstrate that by using the spin-orbit torque, the propagation length of the spin waves in such systems can be increased by nearly a factor of 10, which corresponds to the increase in the spin-wave intensity at the output of a 10 μm long transmission line by three orders of magnitude. We also show that, in the regime, where the magnetic damping is completely compensated by the spin-orbit torque, the spin-wave amplification is suppressed by the nonlinear scattering of the coherent spin waves from current-induced excitations.