Structural, optical and magnetic properties of Er3+, Tb3+: YIG films prepared by sol-gel method

Nanoparticle Y2.8-xTb0.2ErxFe5O12 (x = 0, 0.8, 1.4, 1.8, and 2.2) films were successfully prepared using a sol-gel method. The films were deposited on a quartz substrate, followed by annealing process in air at 900 °C. The XRD patterns revealed the single-phase garnet structure of obtaining films. The results confirmed the successful incorporation of erbium and terbium ions into the YIG structure. The lattice parameter increases at low Er3+ concentration, then decreases with increment of Er3+ ions and the lowest value of 12.34 Å was obtained at (x = 2.2). The sizes of nanoparticles are in the average range from 29 to 46 nm. The addition of Er3+ ions significantly enhanced the transparency (from 64 % to 95 %) in the visible and near infrared region. Magnetic properties study showed that all films are soft ferrimagnetic materials. The saturation magnetization value increased to 190 emu/cm3 at (x=1.4), then decreased dramatically with increment of x content. Coercivity field noticeably increased with the increments of x content.