Title :
Nanometer-Thick Yttrium Iron Garnet Films With Extremely Low Damping
Author :
Houchen Chang ; Peng Li ; Wei Zhang ; Tao Liu ; Hoffmann, Axel ; Longjiang Deng ; Mingzhong Wu
Author_Institution :
Dept. of Phys., Colorado State Univ., Fort Collins, CO, USA
Abstract :
Yttrium iron garnet (YIG) films that are in the nanometer thickness range and show extremely low damping are reported. The films were deposited via sputtering at room temperature and were then annealed in O2 at high temperature. A 22-nm-thick YIG film showed a Gilbert damping constant α = (8.58 ± 0.21) × 10-5, which represents the lowest damping ever reported for nanometer-thick magnetic films. The film had a gyromagnetic ratio of |γ| = 2.83 MHz/Oe and a saturation induction of 4π Ms = 1766 G, which are both very close to those of single-crystal YIG bulk materials. The film had a very smooth surface, with an rms surface roughness of about 0.13 nm.
Keywords :
annealing; damping; garnets; gyromagnetic effect; magnetic thin films; sputter deposition; surface roughness; yttrium compounds; Gilbert damping constant; YIG; annealing; film thickness; gyromagnetic ratio; high temperature effect; nanometer-thick magnetic films; nanometer-thick yttrium iron garnet films; rms surface roughness; single-crystal YIG bulk materials; size 22 nm; smooth surface; sputtering; temperature 293 K to 298 K; Damping; Films; Fitting; Magnetic fields; Magnetic resonance; Sputtering; Current topics; Gilbert damping; ferromagnetic resonance; sputtering; yttrium iron garnet films;
Journal_Title :
Magnetics Letters, IEEE
DOI :
10.1109/LMAG.2014.2350958
