Highly bismuth-substituted, record-performance magneto-optic garnet materials with low coercivity for applications in integrated optics, photonic crystals, imaging and sensing

Garnet multilayer thin film structure with magnetostatically-altered and improved magnetic properties prepared by RF magnetron sputtering

“…The coercivity of Bi 1.8 Lu 1.2 Fe 3.6 Al 1.4 O 12 garnet films of 1 µm thickness prepared onto GGG substrates was only about 45 Oe (green curve), and their saturation magnetization was about 350 Oe, as shown in Fig.4. The almost-linear character of the magnetization curves observed in Bi 1.8 Lu 1.2 Fe 3.6 Al 1.4 O 12 garnet films below magnetic saturation indicates that a significant component of the film's magnetization lies in the film plane [13]. The observed magnetic domain patterns in these two magneto-optic garnet thin-film materials were also totally different, as shown in the inset of Fig.…”

“…This material possesses high uniaxial magnetic anisotropy (with its magnetization direction perpendicular to the film's plane) and also excellent magnetic memory properties. On the other hand, Bi-substituted lutetium iron garnet material of composition Bi 1.8 Lu 1.2 Fe 3.6 Al 1.4 O 12 features a magneto-soft behaviour with almost in-plane magnetization direction and high specific Faraday rotation [13]. In this paper, we report on the properties of an all garnet multilayer structure which is formed by sandwiching a garnet layer of composition type Bi 1 Fig.…”

“…To realise special magnetic behaviours, which are not attainable using single-layer thin films of a chosen garnet material type, we prepare an allgarnet multilayer structure using two record-performance highly-Bi-substituted iron garnet materials having very different magnetic behaviours (magnetic anisotropy, switching fields and saturation magnetizations). The two used Bi-substituted iron garnet (Bi:IG) thin film materials, which have previously been studied by our group in detail [12,13], possess extra-ordinary optical and magneto-optical (MO) properties that are highly attractive for use in various existing and also new applications in optics, photonics and optoelectronics. [12,13].…”

“…The two used Bi-substituted iron garnet (Bi:IG) thin film materials, which have previously been studied by our group in detail [12,13], possess extra-ordinary optical and magneto-optical (MO) properties that are highly attractive for use in various existing and also new applications in optics, photonics and optoelectronics. [12,13]. The present study is aimed at achieving improved magnetic properties in allgarnet multilayers by making triple-layer structures composed of different high-performance material layers that (due to being in close proximity geometrically) interact with each other magnetostatically, leading to improved magnetic properties.…”

Properties of Exchange Coupled All-garnet Magneto-Optic Thin Film Multilayer Structures

“…RF magnetron sputtering allows precise control over the thin film deposition process parameters, thus addressing the issues related to synthesizing high-quality thin films and multilayers wherein each layer’s chemical composition (stoichiometry) must be controlled accurately [10,11,19,20,21]. To investigate the potential of obtaining special magnetic properties that are not attainable easily using single-layer garnet thin films, we prepare all-garnet multilayer structures using two record-performance highly-Bi-substituted iron garnet materials having dissimilar magnetic behaviors (magnetic anisotropy, switching fields and saturation magnetizations).…”