Ferrite Garnet Research Articles

Enhanced Magneto-Optic Properties in Sputtered Bi- Containing Ferrite Garnet Thin Films Fabricated Using Oxygen Plasma Treatment and Metal Oxide Protective Layers.

Magneto-optic (MO) imaging and sensing are at present the most developed practical applications of thin-film MO garnet materials. However, in order to improve sensitivity for a range of established and forward-looking applications, the technology and component-related advances are still necessary. These improvements are expected to originate from new material system development. We propose a set of technological modifications for the RF-magnetron sputtering deposition and crystallization annealing of magneto-optic bismuth-substituted iron-garnet films and investigate the improved material properties. Results show that standard crystallization annealing for the as-deposited ultrathin (sputtered 10 nm thick, amorphous phase) films resulted in more than a factor of two loss in the magneto-optical activity of the films in the visible spectral region, compared to the liquid-phase grown epitaxial films. Results also show that an additional 10 nm-thick metal-oxide (Bi2O3) protective layer above the amorphous film results in ~2.7 times increase in the magneto-optical quality of crystallized iron-garnet films. On the other hand, the effects of post-deposition oxygen (O2) plasma treatment on the magneto-optical (MO) properties of Bismuth substituted iron garnet thin film materials are investigated. Results show that in the visible part of the electromagnetic spectrum (at 532 nm), the O2 treated (up to 3 min) garnet films retain higher specific Faraday rotation and figures of merit compared to non-treated garnet films.

Профильный анализ пленок ферритов-гранатов методом оптической эмиссионной спектроскопии тлеющего разряда

Annotation.The paper presents the results of experiments on the application of the method of optical emission spectroscopy of a glow discharge for the profile analysis of vacuum-deposited single and two-layer films of multicomponent garnet ferrites of various compositions before and after crystallization annealing. The presence of internal and external transition layers was revealed, and the modification of their elemental composition during crystallization, as well as the different sequence of synthesis of individual components in ferrite-garnet heterostructures, was investigated.

Evolutionary mechanism of YBO3 whisker and its effect on the properties of YIG ferrite joint brazed by Bi2O3–B2O3–SiO2–ZnO glass

The Bi2O3–B2O3–SiO2–ZnO glass braze was used to bond the Yttrium iron garnet (YIG) ferrite. The (i) microstructure evolution and (ii) mechanical and dielectric properties of YIG/YIG joints were investigated. The results show that the bonding of YIG ferrite with Bi2O3–B2O3–SiO2–ZnO glass braze was effective at brazing temperature. There were nearly free of defects. At the YIG/glass interface, gray YBO3 whiskers, gray layered YBO3, and black block Fe2O3 phases were observed due to the reaction of the glass braze and YIG ferrite. As the brazing temperature or holding time increased, the gray layered YBO3 phase turned into YBO3 whisker gradually. This is because the B–O bonds of [B3O9] ring in the unit cell of the layered YBO3 are broken and evaluated to [BO4] in the cell of YBO3 whisker. The shear strength reached a maximum of 65 MPa for the joint brazed at 725 °C because of the enhancement effect of YBO3 whisker and Fe2O3 phases. The relative dielectric constant of the joint brazed at 700 °C was about 16, which was close to that of YIG ferrite. Moreover, the dielectric loss of this joint was about 0.005.

Characteristic Features of the Anomalous Magnetic Properties of Some Mixed Terbium–Yttrium Ferrite Garnets at Low Temperatures

This article is devoted to the experimental investigation of the occurrence of the so-called “low-temperature Belov point” T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> predicted previously for the mixed rare earth-yttrium iron garnet compounds RE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3-</sub> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> possessing or not a magnetic compensation point T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">comp</sub> . Isothermal magnetizations MT(H) of two single crystals of Tb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3-x</sub> Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> with rare-earth (RE) = Tb, and x = 1.98, 0.37, were measured in the 4.2-300 K range, using dc magnetic field H up to 100 kOe applied in one or more of the three main crystallographic directions. Anomalies are observed in the region of T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TbIG</sup> ≈ 58 K, the previous estimated value for TbIG (x = 3), in the temperature dependences of the paraprocess susceptibility χ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> , the parameter |b| of the bH <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> term of the quadratic expansion of MT(H) curves, and other pertinent magnetic characteristics. For x = 1.98 with T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">comp</sub> = 137 K and when H is applied along (110), the χ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> - and |b|-maxima take place close to T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TbIG</sup> . The anisotropy of the χ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> -data gives evidence for a spontaneous noncollinear structure around the easy axis of magnetization (111) at 4.2 K. For x = 0.37 which has no T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">comp</sub> point and when H is applied along (100), the χ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> - and |b|-maxima are clearly disturbed by the sign anomalies caused by the noncollinear structure instability mechanism due to the crossing of the Tb <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> levels at the critical point T* = 16 K and by the lower continuous change from the easy axis <;100> to a low-symmetry angular phase (uuw) due to the first spontaneous spin reorientation phase transition at T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SR1</sub> = 40 K. When x decreases from 3 to 0.37, it is found that despite different anisotropy effects of the Tb <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> ion, its magnetic moment m <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Tb</sub> close to T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TbIG</sup> is practically constant (~4.99 in μ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> per Tb <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> ion).

Magnetic behavior of Ga doped yttrium iron garnet ferrite thin films deposited by sol-gel technique

Yttrium Iron Garnet (YIG) ferrites thin films having compositional formula Y3GaxFe5-xO12, where (x = 0, 1, 2, 3, 4) are synthesized by sol gel dip coating technique. XRD, SEM and VSM characterizations are employed to explore structural, morphological and magnetic properties, respectively. XRD showed that Ga is completely doped in YIG and not formed any cluster or other phase with YIG. SEM confirmed the formation of agglomeration of YIG particles. Magnetic parameters like coercivity, remnant squareness, saturation magnetization, magnetic moment, anisotropy constant, initial permeability Y–K angles and microwave frequency were calculated of these films. The coercivity and moderate magnetization suggested that fabricated ferrite films are highly applicable in electromagnetic microwave absorption and frequency agile antenna for wireless communication.

DOMAIN STRUCTURE AND SOME PROPERTIES OF RARE-EARTH GRANITE FERRITES

The crystals of rare-earth garnet ferrites have a complex domain structure, the form of which substantially depends on the crystallographic orientation of the under study sample. Due to the cubic symmetry of rare-earth garnet ferrites, 70, 110, and 180-degree domains can exist in them, and depending on the crystallographic orientation of the sample, the spontaneous magnetization vector in the realized domain configuration can lie in the plane of the sample (“Cotton” domains) perpendicular to the plane of the sample ("Faraday" domains), and make up a certain angle with its plane. According to known data, in all cases, the boundaries between neighboring domains in rare-earth garnet ferrites are the domain walls of the Bloch type

Influence of Gd3+ substitution and preparation technique on the optical and dielectric properties of Y3Fe5O12 garnet synthesized by standard ceramic and coprecipitation methods

Micro-size and nano-size samples of (GdxY3−xFe5O12; x = 0, 0.25, 0.5, 0.75, and 1) garnet ferrites were prepared by the standard ceramic method (CER) and the coprecipitation (COP) method. The influences of Gd3+ doping and preparation methods on the optical and dielectric properties were compared for these micro-size and nano-size compositions for the first time. X-ray diffraction data confirmed the formation of a single phase of the garnet cubic structure for all samples. It was found that there is a good agreement between the theoretical and experimental lattice parameter estimated values. The Fourier transform infrared spectroscopy was used to study the cation distributions among the different crystallographic sites. Moreover, values of energy gap (Eg) for the investigated samples were determined from the diffused reflectance spectroscopy measurements. These values were found to be higher for (COP) samples than for (CER) ones and slightly increased by increasing Gd3+ content in both series prepared via the two techniques. Furthermore, resistivity (ρac), dielectric constant (e′), and dielectric loss (e″) showed a decrease with increasing frequency (f) for all samples. For the samples prepared by (CER) method, ρac increases with increasing Gd3+ content while for the samples prepared by (COP) method, ρac increases for 0 ≤ x ≤ 1 except for the sample x = 0.5. Values of ρac for samples prepared by (COP) method are higher than those prepared by (CER) method. Both e′ and e″ had the reverse behavior of ρac. Obtained results were explained according to different models.

Ferromagnetic and FMR properties of the YIG/TiO2/PZT structures obtained by ion-beam sputtering

For the first time, the YIG (2 μm) /TiO2 (0.2 μm) /PZT (400 μm) structures, where YIG is a polycrystalline layer of yttrium-iron garnet (Y3Fe5O12), PZT is an epitaxially mismatched ferroelectric ceramics based on lead zirconate titanate (PbZr0.45Ti0.55O3) were synthesized by means of ion-beam sputtering – deposition technique. Scanning electron microscopy combined by focused ion-beam method indicates the presence of high-quality plane-parallel YIG/TiO2 and TiO2/PZT interfaces. They were obtained by preliminary ion-beam planarization of the substrate surface using an anti-diffusion layer of titanium dioxide TiO2. Atomic force microscopy showed that planarization allows to achieve a surface smoothness of 10 nm. FMR spectroscopy revealed that the ferrite garnet layers are characterized by a resonance absorption linewidth of ~100 Oe. The linewidth broadening is due to the presence of defects and YIG layer roughness because of the substrate imperfection. The calculated values of the spin-wave damping parameter are of the order of 10−3.The obtained YIG/TiO2/PZT structures can serve as media for the spin waves propagation.

Thermally assisted magnetization control and switching of Dy3Fe5O12 and Tb3Fe5O12 ferrimagnetic garnet by low density current

Current-induced magnetization switching is mainly realized by spin-transfer torque or spin-orbital torque, which usually requires an extremely large current density (more than 105 A/cm2). Here we report a low-energy consumption, stable and reliable, thermal assisted current-induced magnetization switching in devices based on ferrimagnetic RIG (Rare earth garnet ferrite, where R represents rare earth element Dy or Tb). The remanent magnetization of DyIG (Dy3Fe5O12) and TbIG (Tb3Fe5O12) could be switched by applying an external voltage of several volts (corresponding current is tiny and on the order of only 10−3 A/cm2). The remanent magnetization switching of RIG is attributed to the temperature variation (ΔT) induced by the thermal effect of current. The temperature variation ΔT could reach 4.8 K for DyIG at 2 mA/cm2, and could reach 6.54 K for TbIG at 2.4 mA/cm2. The remanent magnetization could be switched from −0.037 to 0.013 emu/g for DyIG, and could be switched from −0.07 to 0.17 emu/g for TbIG. This work might provide a novel way for thermally assisted magnetization switching in ferrimagnetic system.

Electric-field induced micromagnetic structural elements motion in thin ferrite garnet films

We report direct magneto-optical measurements in epitaxial films of bismuth-substituted ferrite garnets that shown the magnetic domain walls can be reversibly changed under an electric field due to the magneto-electric effect. Electric field-induced bending or elongation of domain walls local areas was observed by us using the method of optical polarimetry. Upon removal of the electric field, the domain walls of the magnetic film return to their original configuration.

Anomalies in the magnetic properties of some terbium-yttrium iron garnets at low temperatures

This work is aimed to study the influence of the replacement of the magnetic cations Tb3+ by diamagnetic cations Y3+ on the low-temperature point’, TB predicted by Belov for ferrimagnets with and without magnetic compensation point, Tcomp. Isothermal magnetizations, MT(H) are carried out on single crystals of two mixed terbium-yttrium ferrite garnets TbxY3-xFe5O12 (x = 1.98 and 0.37). The measurements are performed using DC magnetic field, H up to 80 kOe applied along the <111> and <100> crystallographic directions in the 1.5-300 temperature range. From the approximation to the second order of H, the expansion of MT(H) is analyzed on the basis of the T-dependences of the spontaneous magnetization, MS, the paraprocess magnetic susceptibility, χp and the parameter, |b| of the bH2 term. The manifestation of ferromagnetic-and antiferromagnetic-type low-temperature paraprocess and other concomitant effects is observed in the temperature dependences of the derivative, dMS/dT where MS exhibits Néel’s-type curves, i.e., N-type with Tcomp = 137 K for x = 1.98 and P-type without a Tcomp point for x = 0.37). It was established that low-T anomalies appear in the area of TB = 58 K reported before for the pure TbIG. The results obtained for x = 0.37 in the case of the free sphere show that |b| undergo changes at TSR1 = 40 K, TSR2 = 140 K, and TSR3 = 232 K. Thus, we suggest that as T increase, the previous spin reorientation phase transition occurs in a wide T-range, (40-232 K) from the easy axis of magnetization <100> via stable and intermediate low-symmetry angular phases <uuw> towards the high symmetry phase <111>.

Time Aspects of the 180° Pulsed Magnetization Reversal of Ferrite–Garnet Films with Complex Anisotropy

It is shown that a material having four stable positions of the orientation of the magnetization vector makes it possible to double the density of magnetic recording (for example, in MRAM devices) without substantial modifications of production process. This finding is based on investigations of the time aspects of the 180° pulse magnetization reversal of ferrite–garnet films with planar anisotropy, in the region of external fields where the mechanism of uniform rotation of magnetization operates.

A millimeter-wave Bell Test using a ferrite parametric amplifier and a homodyne interferometer

A combined ferrite parametric amplifier and millimeter-wave homodyne interferometer are proposed as an ambient temperature Bell Test. It is shown that the non-linear magnetic susceptibility of the yttrium iron garnet (YIG) ferrite, on account of its narrow line-width Larmor precessional resonance, make it an ideal material for the creation of entangled photons. These can be measured using a homodyne interferometer, as the much larger number of thermally generated photons associated with ambient temperature emission can be screened out. The proposed architecture may enable YIG quantum technology-based sensors to be developed, mimicking in the millimeter-wave band the large number of quantum optical experiments in the near-infrared and visible regions which had been made possible by use of the nonlinear beta barium borate ferroelectric, an analogue of YIG. It is illustrated here how the YIG parametric amplifier can reproduce quantum optical Type I and Type II wave interactions, which can be used to create entangled photons in the millimeter-wave band. It is estimated that when half a cubic centimeter of YIG crystal is placed in a magnetic field of a few Tesla and pumped with 5 Watts of millimeter-wave radiation, approximately 0.5 × 1012 entangled millimeter-wave photon pairs per second are generated by the spin-wave interaction. This means an integration time of only a few tens of seconds is needed for a successful Bell Test. A successful demonstration of this will lead to novel architectures of entanglement-based quantum technology room temperature sensors, re-envisioning YIG as a modern quantum material.

Investigating extraordinary optical transmission and sensing performance through periodic bilayer magneto-plasmonic structure

This paper proposes the phenomenon of extraordinary optical transmission via a magneto-plasmonic nanostructure, which combines magnetic and plasmonic functionalities. The structure includes an active magnetic film magnetized perpendicular to its surface and a plasmonic metal film, perforated with subwavelength circular annular arrays, with a ring placed in the middle of each annular circle. We use the finite element method and the finite-difference time-domain method for simulation of the structure. Numerical analysis shows an improvement in the Faraday rotation and optical transmission, simultaneously, in a magneto-plasmonic structure based on a silver- and bismuth-substituted ferrite garnet. Simultaneous improvement is achieved by coupling the TE and TM waveguide-plasmon modes. The amount of enhancement is adjusted by changing the dimensions, the periodicity of the hole arrays, and the refractive index of the materials filled in the holes. The influence of excitation of the two kinds of plasmon modes and the application of the external magnetic field are used to enhance the optical response. The resulting investigation shows two resonance peaks in the near-infrared range of the Faraday effect spectrum. Because of the strong Faraday rotation coinciding with the dual-band transmission of approximately 90%, the maximum figure of merit can also be obtained. Finally, this structure is investigated as a sensor in different reflective indexes from 1 to 1.5 RIU, and sensitivity of 45.97 nm/RIU was achieved. The potential applications of these nanostructures include, for example, subwavelength optics, optoelectronic devices, biosensing devices, and magneto-optical devices.

Secondary Nuclear Spin Echo Signals in Thin Yttrium Iron Ferrite Garnet Films

The results are presented of experimental and theoretical study of the phenomenon of secondary nuclear spin echo in magnetically ordered materials in which the formation of additional echo signals is due to dynamic hyperfine coupling. Numerical simulation of the effect of the amplitude (ω1) and the durations of the first (t1) and the second (t2) exciting pulses on the echo signals is performed. It is found that the maximum amplitude of the secondary echo is formed under the conditions ω1t1 = 0.5π and ω1t2 ≈ 0.6π. It is shown that secondary echo signals can be observed upon inhomogeneous excitation of the spectral line ω1 ≤ Δω, where Δω is the inhomogeneous spectral line width. At a temperature of T = 4.2 K, additional double-pulse spin 3τ-echo signals from iron nuclei are experimentally observed in an epitaxial yttrium ferrite garnet film enriched with 57Fe magnetic isotope to 96%. The experimentally observed phase relationships between the primary and secondary echo signals, as well as the dependence of the echo signal amplitude on the amplitude and duration of the exciting pulses, are in good agreement with the results of numerical simulation of the dynamics of nuclear magnetization with regard to the dynamic hyperfine coupling. It is shown that the secondary echo exhibits the effect of spectral line narrowing, and the amplitude of the secondary echo is proportional to the nuclear magnetic resonance (NMR) enhancement factor in magnets, η. In the case of 57Fe NMR in an yttrium iron garnet (YIG) film, the amplitude of the 3τ-echo is two to three orders of magnitude smaller than the amplitude of the primary 2τ-echo, which corresponds to η ≈ 440. The detection of weak secondary echo signals proves to be possible due to the use of a phase-coherent NMR spectrometer with digital quadrature detection at the carrier frequency and signal accumulation.

Микроструктура и элементный состав наноразмерных порошков и пленок редкоземельных ферритов-гранатов на основе Sm-=SUB=-3-=/SUB=-Fe-=SUB=-5-=/SUB=-O-=SUB=-12-=/SUB=-

The synthesis of nanostructured powders and films based on rare-earth ferrite garnet Sm3Fe5O12 was carried out with hydrothermal as well as with the method of precipitation of aqueous solutions of nitrates on the substrate surface. Using atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman spectroscopy (Raman), and X-ray phase analysis (XRD), the topology of the surface and the phase composition of the samples were studied. According to AFM and SEM, particle sizes were evaluated and the structural features of powders and films were analyzed. Raman spectroscopy (RS) and X-ray phase analysis were used to examine the chemical composition and crystal structures of synthesized samples. The possibility of simultaneous investigation of the same sample area with AFM methods and Raman spectroscopy made it possible to obtain data of the chemical composition, the presence of impurities and defects, and the shape of macromolecules. Taking into account the set of obtained results, it is shown that materials based on Sm3Fe5O12, due to their structural features and physics-chemical parameters, can be used as filters for industrial sewage treatment.

Вертикальное смещение магнитооптической петли гистерезиса в магнитоплазмонном нанокомпозите

In article the synthesis and investigation results of magneto-optical (MO) properties of thin-film nanocomposite, which is a bismuth-substituted Bi: YIG ferrite garnet layer with Au plasmon nanoparticles are representative. The effect of vertical shift of MO hysteresis loops (relative to the origin of coordinates) was detected with study of MO properties during remagnetization of the magnetoplasmon composite structure. It’s shown that the observed effect is most pronounced near the condition of localized plasmon resonance in the metal nanoparticles system which make up the magnetoplasmonic composite.

Susceptibility and FMR in ferrite garnet epitaxial films for eddy current magneto-optical defectoscopy

The paper presents the magnetic properties of easy plane and easy axis films on the base of Bi - ferrite garnet experimentally investigated by ferromagnetic resonance and the inductive-frequency method. The possibilities and features of the operation of these films as sensors in eddy current magneto-optical introscopy are shown on the example of visualization of linear defects in products made from aluminium alloys.

The Influence of Loading Force on Ultrasonic Drilling Garnet Ferrite

In order to achieve high precision microholes of garnet ferrite, the rotary ultrasonic assisted machining and the tool load matching system were employed. An ultrasonic precise microholes technology experiment platform was built to machine garnet ferrite materials. A series of drilling experiments to machine garnet ferrite were presented in this paper, which were used to explore the influence of cutting force on tool wear. And the holes’ exit aperture and wall surface roughness were applied to be evaluation parameters to explore the effect of loading force on machining quality. As a result, tool wear is aggravates as cutting force increases. And loading force shows different influence tendency on exit aperture size precision and wall surface roughness, the selection of proper loading force does good to control exit aperture size and hole wall surface roughness effictively.

Nonuniform Magnetoelectric Effect in a Nano-Sized Ferromagnetic Film with Surface Anisotropy

A numerical study of the ground state of a ferromagnetic finite film has been performed. The film is characterized by the uniaxial easy-plane bulk magnetic anisotropy and easy-axis surface anisotropy. All calculations were performed for films with parameters of ferrite garnets. The ground state of nano-sized rectangular films (nanocolumns) differing in the cross dimensions is calculated using OOMMF three-dimensional micromagnetic simulation software. The electric polarization is calculated for the vortex magnetization distribution for the ground state. It was found that, in the case of surface anisotropy, the polarization vector component of the film, which is perpendicular to the film plane, is nonzero. A change in the electric polarization upon magnetization of film in an external magnetic field is studied. As the magnetic field increases, the polarization module is also shown to increase to certain values of the field and, after that, decreases to zero. As the cross dimensions of film decreases and the surface anisotropy constant increases, the electric polarization of a nanocolumn increases.