Magnetic field control of light is among the most intriguing methods for modulation of light intensity and polarization on sub-nanosecond timescales. The implementation in nanostructured hybrid materials provides a remarkable increase of magneto-optical effects. However, so far only the enhancement of already known effects has been demonstrated in such materials. Here we postulate a novel magneto-optical phenomenon that originates solely from suitably designed nanostructured metal-dielectric material, the so-called magneto-plasmonic crystal. In this material, an incident light excites coupled plasmonic oscillations and a waveguide mode. An in-plane magnetic field allows excitation of an orthogonally polarized waveguide mode that modifies optical spectrum of the magneto-plasmonic crystal and increases its transparency. The experimentally achieved light intensity modulation reaches 24%. As the effect can potentially exceed 100%, it may have great importance for applied nanophotonics. Further, the effect allows manipulating and exciting waveguide modes by a magnetic field and light of proper polarization.

Ambient oxygen pressure in a pulsed laser deposition process has been observed to have a critical influence on the compositional, crystalline, and electrical properties of Na 0.5 K 0.5 NbO 3 ͑NKN͒ thin films grown onto polycrystalline Pt 80 Ir 20 and SiO 2 ͑native oxide͒/Si͑111͒ substrates. Films prepared at high oxygen pressure ͑ϳ400 mTorr͒ were found to be single phase and highly c-axis oriented. X-ray diffraction -2 scans and rocking curve data show a strong effect of NKN film self-assembling along the ͓001͔ direction regardless of the substrate texture. The high dielectric permittivity of 550, low dissipation factor of less than 3%, and high remanent polarization of 12 C/cm 2 indicate the high ferroelectric quality of the fabricated film. The role of the high-energy component of the erosion products has been proven to be crucial to film performance. On the other hand, films grown at low oxygen pressure ͑ϳ10 mTorr͒ have been found to be mixed phases of ferroelectric NKN and paraelectric potassium niobates. These films have shown superparaelectric behavior: 5% tunability at an electric field of 100 kV/cm, losses as low as 0.3%, and excellent stability to temperature and frequency changes.

Research on magneto-optical photonic crystals has so far been focused on theoretical investigations, because suitable multilayers of iron garnet, the most promising material, have not been readily available. We report the preparation and characterization of a one-dimensional magneto-optical photonic crystal composed of 17 heteroepitaxial layers of bismuth iron garnet and yttrium iron garnet. The magneto-optical Faraday rotation was increased by 140% while transmission decreased by just 16% at the design wavelength of 750 nm as compared with a single-layer bismuth iron garnet film of equivalent thickness. The sample is free of cracks, and good agreement of simulated and experimental spectra of optical transmission and Faraday rotation indicate high quality of the sample and robustness of the preparation technique.

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Recently we sintered by pulsed laser deposition (PLD) technique the epitaxial Fe-deficient yttrium iron garnet (YIG) films with ferromagnetic resonance (FMR) linewidth as narrow as 0.9 Oe, the uniaxial anisotropy as high as Hu=−880 Oe, and demonstrated them feasible for magnetostatic waves band pass filter application [Manuilov et al., J. Appl. Phys. 105, 033917 (2009)]. Here we explore the origin of unusually high noncubic magnetic anisotropy. Using the angular resolved FMR spectroscopy we found that in addition to strong uniaxial anisotropy, cubic magnetic anisotropy experienced almost fivefold reduction compared to standard YIG grown by liquid phase epitaxy. Molecular field theory was employed to calculate saturation magnetization 4πMs, cubic magnetocrystalline K1, and uniaxial anisotropy Ku in garnets with Fe vacancies. The modeling utilizes crystal field parameters that we revealed from earlier published experimental data on diamagnetic ion substituted Y3Fe5O12 and Fe-substituted isomorphous diamagnetic garnets. Consistent single ion anisotropy crystal field theory perfectly fits experimentally observed high saturation magnetization, reduction in cubic, and appearance of strong uniaxial anisotropy in PLD-grown Fe-deficient YIG films. The redistribution of Fe vacancies between different magnetic sublattices was quantified and confirmed that in YIG(111) films ferric ions preferentially leave vacant octahedrally coordinated sites. Simulation of growth induced anisotropy proves the ordering of Fe3+ vacancies within octahedral sites. At equal number of available ferric ions and vacancies, the latter populate the octahedrons with distortion axis perpendicular to the film surface with the probability equal to 0.67. Deformation blockage of octahedral complexes with distortion axes directed along the film surface reduces this probability down to 0.14.

We report on processing and comparative characterization of epitaxial Bi3Fe5O12 (BIG) films grown onto Gd3(ScGa)5O12[GSGG,(001)] single crystal using pulsed laser deposition (PLD) and reactive ion beam sputtering (RIBS) techniques. A very high deposition rate of about 0.8 μm/h has been achieved in the PLD process. Comprehensive x-ray diffraction analyses reveal epitaxial quality both of the films: they are single phase, exclusively (001) oriented, the full width at half maximum of the rocking curve of (004) Bragg reflection is 0.06 deg for PLD and 0.05 deg for RIBS film, strongly in-plane textured with cube-on-cube film-to-substrate epitaxial relationship. Saturation magnetization 4πMs and Faraday rotation at 635 nm were found to be 1400 Gs and −7.8 deg/μm in PLD-BIG, and 1200 Gs and −6.9 deg/μm in RIBS-BIG. Ferromagnetic resonance (FMR) measurements performed at 9.25 GHz yielded the gyromagnetic ratio γ=1.797×107 l/s Oe, 1.826×107 l/s Oe; the constants of uniaxial magnetic anisotropy were Ku*=−8.66×104 erg/cm3, −8.60×104 erg/cm3; the cubic magnetic anisotropy K1=−2.7×103 erg/cm3,−3.8×103 erg/cm3; and the FMR linewidth ΔH=25 and 34 Oe for PLD and RIBS films correspondingly. High Faraday rotation, low microwave loss, and low coercive field ⩽40 Oe of BIG/GSGG(001) films promise their use in integrated magneto-optic applications.

Thin Y3Fe5O12 (YIG) films were pulsed laser deposited onto Gd3Ga5O12 (111) and (001) substrates. Processing conditions were optimized to obtain compressively strained films with a ferromagnetic resonance linewidth at 9 GHz as narrow as 0.9 Oe and high uniaxial magnetic anisotropy Hu=−880 Oe. Several designs of magnetostatic surface wave (MSSW) bandpass filters were fabricated and tested: 0.45 and 0.22 μm thick YIG films lain on transducers alumina board and with microstripe transducers defined directly onto YIG film, with effective antenna areal sizes of 2 and 0.4 mm2. The MSSW filter with 2 mm2 antenna shows, at 7.5 GHz, insertion loss −9 dB and a resonant −3 dB bandwidth as narrow as 12.5 MHz.

Th e critical state in a superconductor with periodic pins has properties similar to the pinch effect, known in plasma physics. It forms a terrace structure around the average flux density gradient, causing stratification of the transport current into the terrace edges where the tlux density gradient is large. Regions of extremely high current thus interlace with regions of near zero current. The appearance of each new terrace inside the superconductor causes the magnetization to change abruptly at rational or periodic fields. This magnetization jump, a new quantum effect in superconductors, corresponds to the addition of one flux quantum threading the pin lattice unit cell. PACS numbers: 74.60.Ge, 52.55.Ez, 74.60.Jg Oscillations of the magnetization of a superconductor at rational or periodic fields have been observed in many superconducting systems having periodic pins [1 -7], indicating the commensuration of the vortex lattice with the pin arrangement.Notably, Hiinnekes et al. found matching to the crystal structure of YBa2Cu307 [7] when the field was parallel to the Cu02 planes, and verified the intrinsic pinning effect in high-temperature superconductors [8,9]. As this example indicates, experimental observations of matching are profound: it is usually very difficult to observe experimentally the subtle interactions between the elastic vortex lattice and the rigid pins. The analysis of matching effects has focused on the commensurability. Present models explain why oscillations appear at rational fields [1,3,10] or at periodic fields [1],but they do not account for the abruptness of the magnetization change.We present a more complete analysis by considering both the effects of commensurability and the role of the critical state [11]in determining the magnetization. We show that the magnetization oscillations are the result of a new quantum effect in superconductors, arising from the competition between commensurability and the Auxon density gradient of the critical state.The critical state of a superconductor having a commensurate vortex-pin lattice breaks up into terraces ["terraced critical state" (TCS)] of a uniformly matched vortex lattice and a current "pinch" (stratification) at the terrace edges. This effect is similar to the pinch effect found in plasma jets, which results in the subdivision of a jet into laces. Within a single terrace the Auxon separation is constant, so the vortex lattice is deformed relative to the local equilibrium given by the macroscopic critical state (CS). An abrupt change in the matching coordination at the terrace edge gives rise to very high Aux density gradients, where current densities approach the theoretical limit. Hence, the global current structure consists of the interlacing of regions of extremely high current with regions of near zero current. The terrace edge is similar to the domain walls found by Pokrovskii and Talanov [12] for two-dimensional incommensurate crystals; here we solve for the mean separation of domain walls by calculating the terrace width. Indeed...