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Abstract: In the present work we study the photonic band structure (PBS) and the polarization state of the Bloch eigenmodes of a two-dimensional magnetophotonic crystal (MPC) with square lattice formed from magneto-optically (MO) active cylinders. The refraction of light at the boundary of the MPC is analyzed. We found that both—the PBS and eigenmodes of the MPC—are most significantly altered by the MO activity in the vicinity of the degeneracies. For this case we demonstrated the possibility of an abrupt change in the propagation direction of light by the application of a magnetic field. For the Bloch wave vectors and frequencies corresponding to non-degenerate branches, the alteration of the PBS is shown to be negligible and eigenmodes almost completely coincide with linearly TE- and/or TM-polarized eigenmodes of the non-magnetic photonic crystal. [Copyright &y& Elsevier]

Abstract: A novel viscosity sensor using a source of vibration was developed. This sensor composes of coil and a moving magnet which is damped by repulsive magnets and liquid. It detects a variation in induced electromotive force for liquids of various viscosities. By using the vibration source at the fixed frequency of 10Hz and at acceleration values 0.28–1.88G, the values of the sensitivity obtained 1.67V/G for the pure water, 0.26V/G for the liquid of 50mm2/s and 0.03V/G for the liquid of 500mm2/s, respectively. [Copyright &y& Elsevier]

Abstract: It was founded using the magneto-optical technique that the domain wall in the iron-based amorphous ferromagnet in its movement experienced enhanced deceleration on the surface compared to the volume. The surface deceleration of the wall intensifies under water molecules adsorption on the sample surface. This effect is explained by the domain wall interaction with magnetic micro-defects observed on the sample surface using a magnetic force microscope. [Copyright &y& Elsevier]

Abstract: The necessary conditions for the observation of the Faraday effect in 2D magneto-photonic crystals are discussed. It is found. that the Faraday effect may be observed in the directions where any couple of the wave vectors of the harmonics consisting the Bloch waves of TE and TM solutions in zero magnetic field are identical. This direction corresponds neither to Faraday nor to Voigt geometry. [Copyright &y& Elsevier]

Planar magnetoplasmonic nanogratings composed of a two-dimensional square array of gold nanoparticles embedded into thin magnetic garnet films are proposed for enhancement of the transverse magneto-optical Kerr effect due to excitation of a quasi-waveguiding mode with light concentrated mostly inside the magnetic film. A proper optimisation of the size and periodicity of plasmonic nanoparticles as well as the thickness of magnetic dielectrics allows spectral tuning of the waveguiding mode leading to the sharp asymmetric resonance in the magneto-optical response in the desired spectral region. [ABSTRACT FROM AUTHOR]

Abstract: Fe–Ce–O films were synthesized by a newly developed electrochemical method called the “metal-oxide co-electrodeposition method”, i.e. the simultaneous deposition of Fe and Ce–O from a reaction solution containing FeSO4, CeCl3, (NH4)2SO4, and l-ascorbic acid. l-ascorbic acid prevents the oxidation of Fe2+ to Fe3+. (NH4)2SO4 acts as the complexing agent for Fe2+ and was effective in avoiding the precipitation of Fe–OH. Therefore, ferromagnetic Fe and Ce–O coexisted films were successfully formed. The Fe–Ce–O films prepared had a uniform surface. The Fe content in the deposited films was subject to change from 0 to 100vol% depending on the concentration of the FeSO4 in the reaction solution. The saturation magnetization of the films fabricated from the reaction solution with (NH4)2SO4 became larger than that of the films prepared from a non-(NH4)2SO4 solution. [Copyright &y& Elsevier]

The fabrication of magnetophotonic crystals (MPC) composed from Bi-substituted yttrium-iron-garnet films separated by silicon oxide layers is presented. The enhancements of the Faraday rotation, second-harmonic generation and nonlinear magneto-optical Kerr effect are observed at the photonic band gap edge. These demonstrate strong light-matter magnetic coupling in MPC and provide the prospects of the new magneto-optical materials for applications. [Copyright &y& Elsevier]

Crystallographic structures and magnetic properties of chemically synthesized FePt nanoparticles, which were firmly stabilized into a monolayer on thermally oxidized Si substrate using 3-amino propyldimethylethoxysilene, were studied. The two-dimensional structure of FePt nanoparticles was confirmed by plan-view high-resolution scanning microscopy observation. The particles transformed from fcc to highly ordered L10 structure by annealing at 800°C under high vacuum with minimal coalescence. From rotational hysteresis loss analysis, a large magnetic anisotropy field of over 80 kOe for the 800°C-annealed film was estimated. The coercivity of the annealed sample was very small and of the order of 102 Oe at room temperature, meanwhile, the remanence coercivity obtained from DC demagnetization measurement was over 11 kOe. This large difference was resulted from the co-existence of Fe-poor particles with different low anisotropy fields in the monolayered film. [Copyright &y& Elsevier]

Abstract: Magneto-optical Kerr effect enhancement in longitudinal and transversal configurations is systematically studied in one- and two-dimensional magnetoplasmonic crystals based on the nanostructured nickel films. Spectral dependences of magneto-optical effects demonstrate resonant features with the Fano-type lineshape in the spectral vicinity of the Wood''s anomaly associated with excitation of surface magnetoplasmons in Voigt and Faraday configurations, respectively. [Copyright &y& Elsevier]

Abstract: We have demonstrated a magneto-optical spatial light modulator in which functionality is realized by (i) heating up to Curie temperature (T c) magneto-optical elements (pixels) with a semiconductor laser and (ii) application of a switching magnetic field. The pixels were made of films of amorphous rare earth–transition metal compounds (TbFe films with T c=403K and DyFe films with T c=343K) having good magneto-optical responses for wavelengths from the visible spectral range. We have found that the magnetization direction of pixels can be modulated with a laser radiation density of 5mJ/cm2 and in a switching magnetic field of 15Oe. [Copyright &y& Elsevier]

Abstract: A large enhancement of the Faraday rotation, which is associated with localized surface plasmon resonance (LSPR), was obtained in a sample with Au nanoparticles embedded in a Bi-substituted yttrium iron garnet (Bi:YIG) film. On a quartz substrate, Au nanoparticles were formed by heating an Au thin film, and a Bi:YIG film was then deposited on them. A sample containing the Au nanoparticles produced by 1000°C heating showed a resonant attenuation with narrower bandwidth in the transmission spectrum than nanoparticles of other samples formed by low-temperature heating. The sharp resonant Faraday rotation angle was 4.4 times larger than the estimated intrinsic Bi:YIG film at the LSPR wavelength; the angular difference was 0.14°. A discrepancy in the bandwidth between the transmission attenuation and the resonant Faraday rotation is discussed. [Copyright &y& Elsevier]

Abstract: The magnetoelastic effect was studied in amorphous ribbons with different compositions. The elastic waves were excited as a result of magnetostriction by the weak AC magnetic field at frequencies till 100kHz. The AC magnetic field was applied locally. A piezoelectric sensor was used to control the amplitude of the standing acoustic vibrations, and a pick-up coil measured the magnetization change. The output signal was measured by the selective nanovoltmeter. The standing waves amplitude and phase distribution depended on external DC magnetic field and stresses in amorphous ribbon. [Copyright &y& Elsevier]

Abstract: Local anodization on a permalloy ( thin film by an atomic force microscope (AFM) in air was studied. Fabrication of uniform structure on the permalloy film was difficult in comparison with that on a Si(100) substrate. On the permalloy film, threshold voltage for the AFM anodization increased until 3h after exposure to air. With passage of time, curves on the permalloy film also changed from metallic behavior to insulating one. In addition, curves varied at positions on the permalloy film. The oxide layer with time- and position-dependencies can induce non-uniform structure in AFM anodization. However, uniformity of structure was able to be improved by using method of fabrication of dots. [Copyright &y& Elsevier]

Abstract: The magnetic properties, especially magnetic softness and anisotropy, of highly magnetostrictive FeSiB amorphous films deposited on glass, silicon, Quartz, and LiNbO3 substrates have been investigated. Although the films were deposited and annealed with the same process condition, there were quite large differences between the magnetic properties with variation of substrate. The prime factor defining the magnetic properties was defined with difference between the thermal expansions of film and substrate. When the film were deposited on the substrate with larger thermal expansion compared to the film, the soft magnetic properties became worse due to perpendicular anisotropy, which was coursed by compressive stress. For example, the coercive force of the film on LiNbO3 substrate was about 30Oe, while the coercive force of the film on silicon substrate was 0.3Oe. [Copyright &y& Elsevier]

Abstract: Magneto-optical transverse Kerr and Faraday effects are studied experimentally and theoretically in one-dimensional magnetophotonic crystals fabricated from a stack of four repetitions of layers of Bi-substituted yttrium iron garnet and SiO2 layers. The results of theoretical calculations in the framework of modified matrices approach are consistent with the obtained experimental data with the exception of the one cusp at 480nm in the transverse Kerr effect spectra. Possible mechanisms of this disagreement are discussed. [Copyright &y& Elsevier]

Abstract: Spectral dependences of Faraday rotation angle in one-dimensional garnet-based magnetophotonic crystals are considered. The enhancement of Faraday angle is demonstrated at the photonic band gap (PBG) edge both theoretically and experimentally. It is shown to be associated with the optical field localization in the magnetic layers of the structure. The advantages of magnetophotonic crystals in comparison with traditional magnetic microcavities are discussed. The specially designed microcavity structures optimized for the Faraday effect enhancement at the PBG edge are suggested. [Copyright &y& Elsevier]

Abstract: Recently, it has been shown that the magnetorefractive effect (MRE) can be significantly enhanced if a layer of material exhibiting MRE is placed inside a photonic crystal to form a defect mode. We propose to use for the MRE enhancement the Salisbury screen as a competitive and much more simple scheme. Since MRE is mostly due to a change of light absorption under magnetization the three-layer Salisbury structure optimized for highest possible absorption inside magnetic layer provides MRE at least two orders of magnitude greater than that for single layer and of the same value or even greater than that for 37-layer photonic crystal. [Copyright &y& Elsevier]