High spin-wave propagation length consistent with low damping in a metallic ferromagnet

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spintronics

Background:

• Magnetic damping is a critical parameter influencing the performance of spintronic devices.
• Achieving ultralow damping is essential for efficient spin-wave propagation and reduced energy dissipation.

Purpose of the Study:

• To investigate and quantify the intrinsic magnetic damping in cobalt-iron (Co25Fe75) heterostructures.
• To explore the relationship between damping and spin-wave propagation in these materials.

Main Methods:

• Broadband ferromagnetic resonance (FMR) spectroscopy in an out-of-plane geometry.
• Measurement of radiative damping and spin pumping effects.
• Brillouin light scattering (BLS) microscopy for spin-wave propagation analysis.

Main Results:

• Ultralow intrinsic magnetic damping (α₀ ≲ 3.18 × 10⁻⁴) was achieved in a 26 nm thick Co25Fe75 heterostructure at room temperature.
• Spin-wave propagation lengths of up to (21 ± 1) μm were measured in the same heterostructure.
• Experimental results show excellent agreement between measured damping and spin-wave propagation.

Conclusions:

• Co25Fe75 heterostructures exhibit exceptionally low magnetic damping at room temperature.
• The observed long spin-wave propagation lengths are consistent with the ultralow damping.
• These findings highlight the potential of Co25Fe75 for high-performance spintronic applications.