Electrical spectroscopy of the spin-wave dispersion and bistability in gallium-doped yttrium iron garnet

Abstract

Yttrium iron garnet (YIG) is a magnetic insulator with record-low damping, allowing spin-wave transport over macroscopic distances. Doping YIG with gallium ions greatly reduces the demagnetizing field and introduces a perpendicular magnetic anisotropy, which leads to an isotropic spin-wave dispersion that facilitates spin-wave optics and spin-wave steering. Here, we characterize the dispersion of a gallium-doped YIG (Ga:YIG) thin film using electrical spectroscopy. We determine the magnetic anisotropy parameters from the ferromagnetic resonance frequency and use propagating spin wave spectroscopy in the Damon-Eshbach configuration to detect the small spin-wave magnetic fields of this ultrathin weak magnet over a wide range of wavevectors, enabling the extraction of the exchange constant $\alpha =1.3(2)\times 10^{-12}$ J/m. The frequencies of the spin waves shift with increasing drive power, which eventually leads to the foldover of the spin-wave modes. Our results shed light on isotropic spin-wave transport in Ga:YIG and highlight the potential of electrical spectroscopy to map out the dispersion and bistability of propagating spin waves in magnets with a low saturation magnetization.

28 pages, 11 figures

References in corpus (4)

• Measurements of the exchange stiffness of YIG films by microwave resonance techniques
• Low damping and microstructural perfection of sub-40nm-thin yttrium iron garnet films grown by liquid phase epitaxy
• Spin-wave logic devices based on isotropic forward volume magneto-static waves
• Electrical spectroscopy of the spin-wave dispersion and bistability in gallium-doped yttrium iron garnet

Cited by in corpus (5)

• Roadmap on Spin-Wave Computing
• Fast long-wavelength exchange spin waves in partially-compensated Ga:YIG
• Electrical spectroscopy of the spin-wave dispersion and bistability in gallium-doped yttrium iron garnet
• Nonlinear erasing of propagating spin-wave pulses in thin-film Ga:YIG
• Spin-wave emission with current-controlled frequency by a PMA-based spin-Hall oscillator