Synthesis of Nanocrystalline Yig Using Microwave-Hydrothermal Method

Abstract

The aim of present research is to study the influence of sintering temperature on the preparation of nanocrystalline Yttrium Iron garnet (YIG) with improved magnetic properties. The nanocrystalline YIG powders were synthesized using Microwave-Hydrothermal (M-H) method. The synthesized powders were characterized using X-ray diffraction (XRD) and Transmission Electron Microscope (TEM). The powders were sintered at various temperatures using microwave sintering method. The sintered samples were characterized using XRD. The complex permeability, dielectric constant and loss tangent of sintered YIG ceramic were also measured and discussed in this paper

Indirect coupling of magnons by cavity photons

“…Forward scattered intensities, i.e., θ = π/2, φ = π, and scattering efficiency factors are convenient and observable measures of the microwave-matter coupling. In order to compare our results with recent experiments, we adopt parameters for YIG with gyromagnetic ratio γ/(2π) = 28 GHz/T, saturation magnetization µ 0 M s = 175 mT [44], Gilbert damping constant α = 3 × 10 −4 [28][29][30], and relative permittivity sp / 0 = 15 [45]. The incident microwave radiation comes from the positive x direction (θ k = π/2 and φ k = 0) and is linearly polarized such that its electric/magnetic components are in the −z/y directions (static magnetic field and magnetization H 0 z).…”

Magnetic spheres in microwave cavities

“…, and relative permittivity [42] / 0 = 15. Without loss of generality we consider microwaves incident from the positive x direction (θ k = π/2 and φ k = 0) and polarization (p θ ,p φ ) = (1,0), so its electric/magnetic components are in the −z/y directions (static magnetic field and magnetization H 0 z).…”

Circulating cavity magnon polaritons

“…where k = ω/c is the wave number of light in vacuum. For YIG, (ε r , μ r ) = (15, μ M ) [37] inside the magnets and (ε r , μ r ) = (1, 1) in the rest of the cavity. The energy transported by propagating electromagnetic waves is captured by the cycle-averaged Poynting vector P = 1 2 Re(E * × H) [36], where the asterisk symbol denotes the complex conjugate.…”