Multi-layered Fe Films for Microwave Applications

Abstract

The microwave permeability of multi-layered Fe films is under study. The multilayer films are found to possess more rigid magnetic structure and larger damping factor of ferromagnetic resonance compared to those of single-layer films. Bulk materials with high microwave permeability may be produced as laminated structures of these multi-layer ferromagnetic films. In the paper, experimental data are presented on the microwave permeability of such laminated regular structures based on Fe films. Possible technical applications of the materials under study include thin wideband radar absorbers and miniaturized patch antennas.

Tailoring Diverse Microwave Properties of High Magnetic Moment FeCo Nanofilms through Different Atom Arrangements

“…Due to the use of the undoped FeCo, these results are much larger than those obtained with other doping methods or materials (e.g. Fe, FeAlB, NiZnCo) …”

“…Ferromagnetic nanofilms with high saturation magnetization (M s ), particularly FeCo alloys with the highest M s value (theoretically 2.45 T), are promising candidates for emerging compact high-performance magnetoelectronic, microwave, and spintronic devices. [1][2][3] Thin films with diverse and specific dynamic microwavep roperties are essential components for these different applications.F or example, ah igh-frequency mobile phone requires af erromagnetic element of high resonant frequency( f r ); [4] at hin single-band microwavea bsorber requires ferromagnetic films with large resonance-type permeability (m), whereas ab roadband absorber requires films with wide frequencyd ispersion or large relaxation-type m. [3,5] The demand for aw ider ange of functions poses challenges for both scientific understanding [6,7] and fabrication [8][9][10] of these thin films, in particular, for applications in gigahertz (GHz) range. [9,11] Hence despite being one of the earliestt hemes in magnetism, [12] the topic of ferromagnetic thin films for high-frequency applications still generates much interestf rom scientists and engineers.…”

“…For example, a high‐frequency mobile phone requires a ferromagnetic element of high resonant frequency ( f r ); a thin single‐band microwave absorber requires ferromagnetic films with large resonance‐type permeability ( μ ), whereas a broadband absorber requires films with wide frequency dispersion or large relaxation‐type μ . The demand for a wide range of functions poses challenges for both scientific understanding and fabrication of these thin films, in particular, for applications in gigahertz (GHz) range . Hence despite being one of the earliest themes in magnetism, the topic of ferromagnetic thin films for high‐frequency applications still generates much interest from scientists and engineers .…”

Design of a Tunable Polarizer Using a One–dimensional Nano Sized Photonic Bandgap Structure

“…PCs have drawn much attention as a new kind of optical materials [12,13]. These materials have many potential applications in optoelectronics and optical communication [13][14][15][16][17][18][19][20][21][22][23][24][25][26].…”

Microwave/Millimeter-Wave Generation Using Multi-Wavelength Photonic Crystal Fiber Brillouin Laser

“…Other applications like its materials permeability [3], imaging for iatrology [4] and industrial composites processing [5,6] are also developing. So a good source is very necessary.…”