06841 06847 06848 06849 06850
Публікації, в яких представлені результати проекту |
068 Electric-field induced ferromagnetic phase in paraelectric antiferromagnets |
Автори: | Maya D. Glinchuk, Eugene A. Eliseev, Yijia Gu, Long-Qing Chen, Venkatraman Gopalan, and Anna N. Morozovska | |
Реферат: | The phase diagram of a quantum paraelectric antiferromagnet EuTiO3 under an external electric field is calculated using Landau-Ginzburg-Devonshire theory. The application of an electric field E in the absence of strain leads to the appearance of a ferromagnetic (FM) phase due to the magnetoelectric (ME) coupling. At an electric field greater than a critical field, Ecr, the antiferromagnetic (AFM) phase disappears for all considered temperatures, and FM becomes the only stable magnetic phase. The calculated value of the critical field is close to the values reported recently by Ryan et al. [Nat. Commun. 4, 1334 (2013)] for EuTiO3 film under a compressive strain. The FM phase can also be induced by an E-field in other paraelectric antiferromagnetic oxides with a positive AFM-type ME coupling coefficient and a negative FM-type ME coupling coefficient. The results show the possibility of controlling multiferroicity, including the FM and AFM phases, with help of an electric field application. | |
Ключові слова: | ferromagnetic phase, paraelectric antiferromagnets, phase diagram, Landau-Ginzburg-Devonshire theory | |
Видання: | Phys. Rev. B 89(6) , 014112 | | | 2014,
014112,англійська |
068 Ferromagnetism induced by magnetic vacancies as a size effect in thin films of nonmagnetic oxides |
Автори: | M. D. Glinchuk, E. A. Eliseev, V. Khist, A. N. Morozovska | |
Реферат: | A theory of magnetization induction in thin films of binary nonmagnetic oxides has been developed. We show that the origin and the main peculiarities of magnetization experimentally observed in thin films of such nonmagnetic oxides as SnO2, CeO2, Al2O3, ZnO, MgO, and HfO2 can be explained if oxygen vacancies are considered as magnetization sources. Our calculations have shown that the oxygen vacancies become magnetic at the film–substrate interface, and a long-range ferromagnetic order appears in thin films at room and higher temperatures. The role of substrate turns out to be extremely important for the accumulation of magnetic vacancies taking place owing to the film-substrate misfit stress. The vacancy accumulation has been shown to result in the film magnetization increase, which agrees with experimental data. | |
Ключові слова: | Misfit strain; Nonmagnetic oxides; Magnetic defects | |
Видання: | Thin Solid Films, 534 | | | 2013,
685-692 ,англійська |
068 New multiferroics based on EuxSr1-xTiO3 nanotubes and nanowires |
Автори: | Eugene A. Eliseev1, Maya D. Glinchuk1, Victoria V. Khist1, Chan-Woo Lee2, Chaitanya S. Deo3, Rakesh K. Behera3,a) and Anna N. Morozovska | |
Реферат: | Using Landau-Ginzburg-Devonshire theory, we have addressed the complex interplay between structural antiferrodistortive order parameter (oxygen octahedron rotations), polarization and magnetization in EuxSr1−xTiO3 nanosystems. We have calculated the phase diagrams of EuxSr1−xTiO3 bulk, nanotubes and nanowires, which include the antiferrodistortive, ferroelectric, ferromagnetic, and antiferromagnetic phases. For EuxSr1−xTiO3 nanosystems, our calculations show the presence of antiferrodistortive-ferroelectric-ferromagnetic phase or the triple phase at low temperatures (≤10 K). The polarization and magnetization values in the triple phase are calculated to be relatively high (~50 μC/cm2 and ~0.5 MA/m). Therefore, the strong coupling between structural distortions, polarization, and magnetization suggests the EuxSr1−xTiO3 nanosystems as strong candidates for possible multiferroic applications. | |
Ключові слова: | Polarization, Nanotubes, Nanowires, Ferromagnetism, Nanostructures | |
Видання: | J. Appl. Phys. 113 | | | 2013,
024107,англійська |
068 Nanoferroics |
Автори: | M.D. Glinchuk, A.V. Ragulya, V.A. Stephanovich | |
Реферат: | The book is devoted to nanoferroics i.e. to the materials with phase transitions in the form of nanostructures. Because of essential drive towards smaller devices nowadays in the nearest future these materials are expected to substitute for traditional ferroics broadly used in the modern electronic devices. It was initially assumed that as the size of nanoparticles or a film thickness continued to decrease the order parameters (electric polarization, magnetization, mechanical deformation) of phase transitions, which are known to be the collective phenomenon, would vanish and so the useful for application properties related to them. In reality the behavior appeared to be more complex with the conservation of the order parameters up to lattice constant sizes under some conditions as experimental and theoretical investigations had shown. To pour light on all these problems in the book the results of theoretical, experimental investigations of nanoferroics and methods of their fabrication are generalized. The background of the book are the results of many years work of the book authors in the field of ferroics properties size effects theory, the experimental study of nanosize particles and thin films as well as in nanomaterials technology. Nowadays achievements of world science in nanoferroics are also represented. The data about structure and properties of nanoferroics are systematized and some new properties absent in bulk are forecasted. The description of technology of nanoferroics fabrication with attention to the competition of the mechanisms of new phase nucleation and growth is given. | |
Ключові слова: | nanoferroics, phase transitions, nanostructures, order parameters, size effects theory | |
Видання: | Springer | | | 2013,
1-378,англійська |
068 Local structure and electron spin resonance of copper doped SrTiO3 ceramics |
Автори: | V. V. Laguta, O. I. Scherbina, E. P. Garmash, V. N. Pavlikov, M. V. Karpec, M. D. Glinchuk, G. S. Svechnikov | |
Реферат: | We report X-ray diffraction and electron spin resonance (ESR) measurements of the effect of SrTiO3 ceramics doping using Cu2+ ions. ESR measurements reveal two kinds of Cu2+ centers in weakly (0.2–0.5 mol % Cu) doped SrTiO3. Both kinds of centers have been attributed to Cu2+ at octahedral Ti sites and possibly associated either with a nearest-neighboring oxygen vacancy (center #1) or some other positively charged defect (center #2). The ESR spectra of the above centers are described by the following spin Hamiltonian parameters: g|| = 2.263(1), g = 2.041(1), A|| = 170(1) × 10−4 cm−1, A = 27(1) × 10−4 cm−1 (center #1) and g|| = 2.334(1), g = 2.059(1), A|| = 137(1) × 10−4 cm−1, A ≈ 0(1) × 10−4 cm−1 (center #2). For copper concentration larger than 2 mol %, the antiferromagnetic SrCu3Ti4O12 (SCTO) phase has been detected by both X-ray diffraction and ESR. Its volume increases with increase of Cu concentration reaching about 17 % at Cu doping of 20 mol%. The composite SrTiO3–SCTO ceramics exhibits substantial magnetocapacitance effect, which could be enhanced by electrostriction of SrTiO3. | |
Ключові слова: | nanoferroics, phase transitions, nanostructures, order parameters, size effects theory | |
Видання: | Journal of Materials Science June 2013, Volume 48, Issue 11 | | | 2013,
4016-4022,англійська |
068 Roto-flexoelectric coupling impact on the phase diagrams and pyroelectricity of thin SrTiO3 films |
Автори: | Anna N. Morozovska, Eugene A. Eliseev, Svetlana Bravina, Albina Y Borisevich, Sergei V Kalinin | |
Реферат: | The influence of the flexoelectric and rotostriction coupling on the phase diagrams of ferroelastic-quantum paraelectric SrTiO3 films was studied using Landau-Ginzburg-Devonshire (LGD) theory. The phase diagrams in coordinates temperature - film thickness were calculated for different epitaxial misfit strains. Tensile misfit strains stimulate appearance of the spontaneous out-of-plane structural order parameter (displacement vector of an appropriate oxygen atom from its cubic position) in the structural phase. Compressive misfit strains stimulate appearance of the spontaneous in-plane structural order parameter. Gradients of the structural order parameter components, which inevitably exist in the vicinity of film surfaces due to the termination and symmetry breaking, induce improper polarization and pyroelectric response via the flexoelectric and rotostriction coupling mechanism. Flexoelectric and rotostriction coupling results in the roto-flexoelectric field that is antisymmetric inside the film, small in the central part of the film, where the gradients of the structural parameter are small, and maximal near the surfaces, where the gradients of the structural parameter are highest. The field induces improper polarization and pyroelectric response. Penetration depths of the improper phases (both polar and structural) can reach several nm from the film surfaces. An improper pyroelectric response of thin films is high enough to be registered with planar-type electrode configurations by conventional pyroelectric methods.
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Ключові слова: | coupling impact, paraelectric SrTiO3 films, . Flexoelectrics and
rotostriction
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Видання: | Journal of Applied Physics, 04/2012; 112(6) | | | 2012,
1063/1.4752397,англійська |
068 Interfacial polarization and pyroelectricity in antiferrodistortive structures induced by a flexoelectric effect and rotostriction |
Автори: | Anna N. Morozovska, Eugene A. Eliseev, Maya D. Glinchuk, Long-Qing Chen, and Venkatraman Gopalan | |
Реферат: | Theoretical analysis based on the Landau-Ginzburg-Devonshire theory is used to show that the combined effect of flexoelectricity and rotostriction can lead to a spontaneous polarization and pyroelectricity in the vicinity of antiphase boundaries, structural twin walls, surfaces, and interfaces in the octahedrally tilted phase of otherwise nonferroelectric perovskites such as CaTiO3, SrTiO3, and EuTiO3. As an example, we numerically demonstrate a spontaneous polarization and pyroelectric response at the SrTiO3 antiphase and twin boundaries at temperatures lower than the antiferrodistortive structural phase transition temperature of TS∼105 K in agreement with previously unexplained experimental results. At temperatures lower than effective Curie temperature TC∗ (∼25 K for twins and ∼50 K for antiphase boundaries) biquadratic coupling between oxygen octahedron tilt and polarization vectors essentially enhances the polarization induced by the combined flexoelectric and rotostriction effects near the hard domain wall. Biquadratic coupling cannot induce polarization inside easy twins and antiphase boundaries; their polarization and pyroelectricity originates below TS from the built-in flexoelectric field. The spontaneous polarization reaches the values ∼0.1–5 μC/cm2 at the SrTiO3 antiphase boundaries and twins without free charges. A principal difference between the influence of biquadratic and flexoelectric couplings on the interfacial polarization is the following: the biquadratic coupling induces bistable ferroelectric polarization inside hard antiphase boundaries and hard twins below TC∗, while the flexoelectric coupling induces improper spontaneous polarization via the flexoelectric field below TS. | |
Ключові слова: | Flexoelectric effect, antiferrodistortive phase, antiphase and twin boundaries
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Видання: | Phys. Rev. B 85 | | | 2012,
094107,англійська |
068 Влияние поверхности на тензор модулей упругости |
Автори: | Глинчук М.Д., Скороход В.В., Елисеев Е.А., Хист В.В., Зауличный В.Я. | |
Реферат: | Розглянуто зміни незалежних компонент тензорів модулів пружності поблизу плоских поверхонь для всіх 32 кристалографічних об'ємних класів. Розрахунок проведено для тензорів четвертого рангу модулів пружності та податливості на основі теорії симетрії, що враховує вплив елементів симетрії групи на компоненти тензорів. Встановлено збільшення числа ненульових компонент завдяки зниженню симетрії поблизу поверхні. Зокрема, до існуючих в об'ємі трьох незалежних пружних модулів (c11, c12, c44) слід додати c33, c13 та c66 для поверхні типу (100) та нові ненульові компоненти c14, c22=−c14, c56=−c14 для поверхні типу (111). Порівняльний аналіз величин тензорів пружності в об'ємі та поблизу поверхні показав, що співвідношення Коші не виконуються у наноструктурних матеріалах через втрату просторової інверсії атомів поблизу поверхні. На основі проведених раніше експериментальних досліджень та першопринципних розрахунків встановлено, що вплив поверхні є значним для розмірів, що не перевищують 100 нм. | |
Ключові слова: | Порiвняльний аналiз, тензори пружностi, наноструктурні матеріали, поверхня | |
Видання: | Доповiдi Нацiональної академiї наук України, 2011, №12 | | | 2012,
72-78,російська |
068 Anion vacancy-driven magnetism in incipient ferroelectric SrTiO3 and KTaO3 nanoparticles |
Автори: | Eliseev E.A., Morozovska A.N., Glinchuk M.D., Blinc R. | |
Реферат: | We predict that undoped nanoparticles (size ≤ 10–100 nm) of incipient ferroelectrics without any magnetic ions can become ferromagnetic even at room temperatures due to the inherent presence of a new type of magnetic defects with spin S = 1, namely oxygen vacancies, where the magnetic triplet state is the ground state in the vicinity of the surface (magnetic shell), while the nonmagnetic singlet is the ground state in the bulk material (nonmagnetic core). In particular, for a particle radii R less than the critical radius Rc (T) ferromagnetic long-range order appears in a shell region of thickness 5–50 nm once the concentration of magnetic defects N exceeds the magnetic percolation threshold Np. At vacancy concentrations N < Np and radii R < Rc(T), short-range ferromagnetic order and consequently a spin glass state may appear. For particle radii R > Rc(T), only the paramagnetic phase is possible. | |
Ключові слова: | Vacancies; ferromagnetism; nanoparticles; permittivity; dielectrics | |
Видання: | J. Appl. Phys. 109 | | | 2011,
094105,англійська |
068 Surface-induced magnetization of the solids with impurities and vacancies |
Автори: | Morozovska A. N., Eliseev E. A., Glinchuk M. D., Blinc R. | |
Реферат: | Using the quantum-mechanical approach combined with the image charge method we calculated the lowest energy levels of the impurities and neutral vacancies with two electrons or holes located in the vicinity of flat surface of different solids. Unexpectedly we obtained that the magnetic triplet state is the ground state of the impurities and neutral vacancies in the vicinity of surface, while the nonmagnetic singlet is the ground state in the bulk, for e.g. He atom, Li+, Be++ ions, etc. The energy difference between the lowest triplet and singlet states strongly depends on the electron (hole) effective mass μ, dielectric permittivity of the solid ε2 and the distance from the surface z0. For z0=0 and defect charge ∣Z∣=2 the energy difference is more than several hundreds of Kelvins at μ=(0.5−1)me and ε2=2–10, more than several tens of Kelvins at μ=(0.1−0.2)me andε2=5–10, and not more than several Kelvins at μ<0.1me and ε2>15 (me is the mass of a free electron). Pair interaction of the identical surface defects (two doubly charged impurities or vacancies with two electrons or holes) reveals the ferromagnetic spin state with the maximal exchange energy at the definite distance between the defects (~5–25 nm). We estimated the critical concentration of surface defects and transition temperature of ferromagnetic long-range order appearance in the framework of percolation and mean field theories, and RKKY approach for semiconductors like ZnO. We obtained that the nonmagnetic singlet state is the lowest one for a molecule with two electrons formed by a pair of identical surface impurities (like surface hydrogen), while its next state with deep enough negative energy minimum is the magnetic triplet. The metastable magnetic triplet state appeared for such molecule at the surface indicates the possibility of metastable ortho-states of the hydrogen-like molecules, while they are absent in the bulk of material. The two series of spectral lines are expected due to the coexistence of ortho- and para-states of the molecules at the surface. We hope that obtained results could provide an alternative mechanism of the room temperature ferromagnetism observed in TiO2, HfO2, and In2O3 thin films with contribution of the oxygen vacancies. We expect that both anion and cation vacancies near the flat surface act as magnetic defects because of their triplet ground state and Hund's rule. The theoretical forecasts are waiting for experimental justification allowing for the number of the defects in the vicinity of surface is much larger than in the bulk of as-grown samples. | |
Ключові слова: | Impurities and vacancies; Surface; Image charges | |
Видання: | Physica B: Condensed Matter Volume 406, Issue 9, 15 April 2011 | | | 2011,
1673–1688,англійська |
068 Linear magnetoelectric coupling and ferroelectricity induced by the flexomagnetic effect in ferroics |
Автори: | E.A. Eliseev, M.D. Glinchuk, V. Khist, V.V. Skorokhod, R. Blinc, A.N. Morozovska | |
Реферат: | We show that the flexomagnetic effect leads to new linear flexomagnetoelectric (FME) coupling in bulk and nanosized materials, where the polarization and (anti)magnetization vectors are spatially inhomogeneous due to external or internal forces. The linear FME coupling is proportional to the product of the gradients of (anti)magnetization, polarization, flexomagnetic, and flexoelectric tensors. Due to the gradient nature, the physical sources of the FME coupling are quite different from the well-known linear and quadratic magnetoelectric (ME) couplings. In nanosized systems with intrinsic spontaneous gradients of the (anti)magnetization and polarization the linear FME coupling induces the size-dependent linear ME coupling between the average polarization and magnetization. The linear ME coupling coefficient is inversely proportional to the characteristic size of the system (film thickness, particle radius, etc.), magnetization, and polarization extrapolation lengths. The flexomagnetic effect may lead to improper ferroelectricity in bulk and nanosized (anti)ferromagnetics via the new linear and nonlinear FME coupling. Thus we propose a new mechanism based of the flexomagnetic effect for creation of linear MEs, multiferroics, namely improper ferroelectrics-(anti)ferromagnetics. The FME coupling between the polarization and magnetization strongly influences the dielectric susceptibility and ME tunability of multiferroics. Using the symmetry theory we calculate the evident form of the flexomagnetic effect tensor for all 90 bulk magnetic classes and showed that 69 of them are flexomagnetic. Due to the symmetry lowering all 90 bulk magnetic classes become flexomagnetic in the vicinity of surfaces/interfaces. Consequently the flexomagnetic effect strongly increases the number of the ME multiferroic materials. | |
Ключові слова: | flexomagnetic effect, ferroics, nanosized materials, magnetoelectric coupling | |
Видання: | Phys. Rev. B 84 | | | 2011,
174112,англійська |
068 Ferroelectricity and ferromagnetism in EuTiO3 nanowires |
Автори: | Morozovska A. N., Glinchuk M. D., Behera R. K., Zaulychny B. Y., Deo C. S., Eliseev E. A. | |
Реферат: | We predicted the ferroelectric–ferromagnetic multiferroic properties of EuTiO3 nanowires and generated the phase diagrams in coordinates of temperature and wire radii. The calculations were performed within the Landau-Ginzburg-Devonshire theory with phenomenological parameters extracted from tabulated experimental data and first-principles calculations. Since bulk EuTiO3 is antiferromagnetic at temperatures lower than 5.5 K and paraelectric at all temperatures, our goal was to investigate the possibility of inducing the ferroelectric and ferromagnetic properties of EuTiO3 by reducing the bulk to nanosystems. Our results indicate that ferroelectric spontaneous polarization of ~0.1–0.5 C/m2 is induced in EuTiO3 nanowires due to the intrinsic surface stress, which is inversely proportional to the nanowire radius. Spontaneous polarization exists at temperatures lower than 300 K for wire diameter of ~4 lattice constants with 10 N/m surface stress coefficient. Due to the strong biquadratic magnetoelectric coupling, the spontaneous polarization in turn induces the ferromagnetic phase at temperatures lower than 30 K for 2-nm nanowire and at temperatures lower than 10 K for 4-nm nanowire in EuTiO3. Thus, we predicted that the EuTiO3 nanowires can be the new ferroelectric–ferromagnetic multiferroic. | |
Ключові слова: | EuTiO3 nanowires, ferroelectric–ferromagnetic, multiferroic properties, phase diagrams | |
Видання: | Phys. Rev. B 84 | | | 2011,
205403,англійська |
068 Surface-induced piezomagnetic, piezoelectric and linear magnetoelectric effects in nanosystems |
Автори: | Eliseev E. A., Morozovska A. N., Glinchuk M. D., Zaulychny B.Y., Skorokhod V. V., Blinc R. | |
Реферат: | Using symmetry theory we explore how symmetry breaking inevitably present in the vicinity of any surface gives rise to spontaneous surface piezomagnetic, piezoelectric, and magnetoelectric effects. The large surface-to-volume ratio makes the surface symmetry effects dominant in small enough nanosystems. As a result piezomagnetism, piezoelectricity, and strong size-dependent linear magnetoelectric coupling are predicted in nanomaterials, which are nonpiezomagnetic and/or nonpiezoelectric in the bulk, but belong to the one of the existing 90 bulk magnetic classes, e.g., among a wide class of cubic binary oxides such as MnO, FeO, CoO, NiO, EuO, PrO, and Er2O3. | |
Ключові слова: | symmetry theory, symmetry breaking, surface, nanosystems, magnetoelectric effects | |
Видання: | Phys. Rev. B 82 | | | 2010,
085408,англійська |
068 Analytical prediction of size-induced ferroelectricity in BaO nanowires under stress |
Автори: | A. N. Morozovska, E. A. Eliseev, M. D. Glinchuk, R. Blinc | |
Реферат: | We predict that a ferroelectric phase can be induced in otherwise nonferroelectric binary oxides like BaO, EuO and Er2O3 by a strong enough stress σ ~ μ/R present under the curved surface in nanowires due to intrinsic surface stress μ. Our analytical calculations performed within the Landau-Ginzburg-Devonshire theory prove that BaO nanowires of radius R ~ (1–10) nm can be ferroelectric at room temperatures with spontaneous polarization values ~0.5 C/m2 for typical surface stress coefficients μ ~ (10–50) N/m. The same phenomena could lead to high temperature magnetoelectric effect in nanosystems of magnetic binary oxides | |
Ключові слова: | size-induced ferroelectricity, nanowires, stress, nonferroelectric binary oxides | |
Видання: | Phys. Rev. B 81 | | | 2010,
092101,англійська |
068 Magnetic and electrical properties of ferromagnetic nanocomposites based on Co nanoparticles in Al2O3 matrix |
Автори: | M. V. Radchenko, G. V. Lashkarev, M. E. Bugaiova, V. I. Sichkovskyi, V. I. Lazorenko, Y. A. Stelmakh, L. A. Krushynskaya, W. Knoff, T. Story, S. P. Kolesnik, N. I. Danylenko | |
Реферат: | Magnetic, structural, and electrical properties are reported for ferromagnetic nanocomposites (FMNC) consisting of nanometer size Co ferromagnetic nanoparticles (NP) embedded in Al2O3 dielectric matrix. Cox(Al2O3)100−x FMNC with x = 7.8, 28.2, and 42.2 at.% were obtained in the form of (1–5) µm thick films by modified electron beam physical vapor deposition of Al2O3 and Co vapors condensing on policor substrate at temperatures 100–400 °C. Magnetic properties of these FMNC studied by SQUID magnetometry and ferromagnetic resonance (FMR) methods revealed paramagnetic properties for layers with x = 7.8 at.%, superparamagnetic behavior for x = 28.2 at.%, and ferromagnetic state for the highest Co concentration studied x = 42.2 at.%. Temperature dependence of electrical conductivity in FMNC with low Co content was found to follow the Mott law for variable range hopping mechanism. Magnetic field dependence of resistivity revealed a negative magnetoresistance effect. These results confirm the effectiveness of the applied technology for the preparation of Cox(Al2O3)100−x FMNC. | |
Ключові слова: | electron beam physical vapor deposition;ferromagnetic transition metals;magnetic nanoparticles;magnetoresistance | |
Видання: | Physica status solidi (b) Volume 248, Issue 7 | | | 2011,
1619–1622,англійська |
Конференції, семінари, читання, на яких представлені результати проекту |
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068 3.1. Багатофункціональні наноматеріали Мета:Розробка методів синтезу та створення технології виготовлення наносистем з наночастками різних розмірів і форм, з магнітними або сегнетоелектричними фазами та аномальними властивостями на основі матеріалів, які не мають таких фаз та властивостей в об'ємному стані. Очікувані результати:Випуск нового виду продукції: методів, теорій Етап 1:Розробка методів синтезу наночасток немагнітних матеріалів типу MgO, CaO, BaO з розмірами 1-20 нм та дослідження їх магнітних властивостей; вдосконалення існуючих методів синтезу нанодисперсних порошків віртуальних сегнетоелектриків SrTiO3, CaTiO3, KTaO3 з домішками Mn2+ або Cu2+ або Li+ з розмірами часток від 5 нм до 50 нм. Оптимізація умов вирощування феромагнітних нанокомпозитів (ФМНК) Co/Al2O3 та дослідження їх властивостей. Етап 2:Розробка методів синтезу та технології виготовлення нанодисперсних порошків немагнітних матеріалів ZrO2, Al2O3, ZnO, а також - порошків і високощільної магнітоелектричної мікро- і нанозеренної кераміки на основі сполук KTaO3 з домішками Cu, Mn; дослідження впливу розмірів часток порошків на появу магнітоелектричного та п’єзомагнітного ефектів. Дослідження впливу форми, дисперсії ФМНЧ за розмірами та їх середнього розміру на величину від’ємного та додатного МО. Оптимізація дисперсії за розмірами для досягнення максимального МО у слабких та середніх магнітних полях. Етап 3:Розробка методів синтезу і технології виготовлення нанодисперсних з різною морфологією порошків магнітних матеріалів (MnO, СuO), вивчення критичних розмірів, порошків магнітних матеріалів (MnO, СuO), які можуть забезпечити появу значних магнітоелектричного та п’єзомагнітного ефектів; дослідження фазової діаграми та властивостей отриманих нанозеренних магнітних матеріалів у залежності від середнього розміру наночасток, типу та концентрації домішок у широкому температурному та частотному інтервалі. Дослідження впливу фазового стану ФМНЧ на величину від'ємного та додатного МО. Етап 4:Експериментальне та теоретичне вивчення типу домішок та дефектів у наносистемах, що мають привести до появи магнітної або сегнетоелектричної фази з параметрами (температура фазового переходу, поляризація, намагніченість тощо), керованими типом домішок та дефектів, а також розмірами наносистеми.Дослідження магнітоелектричних характеристик синтезованих нанопорошків. Розробка теорії для опису особливостей розмірних ефектів, фазових діаграм та властивостей наноматеріалів на основі віртуальних сегнетоелектриків з магнітними та немагнітними домішками, встановлення умов виникнення магнітоелектричної фази. Формування магніточутливих структур ФМНК/напівпровідник, з метою збільшення магніточутливості цих структур в слабких магнітних полях. Етап 5:Узагальнення отриманих результатів, рекомендації відносно геометрії та розмірів наноструктур з новими властивостями, що відсутні в об’ємних матеріалах. Створення експериментальних зразків нанозеренних керамічних матеріалів та їх лабораторних прототипів з набором параметрів, необхідних для використання у новітніх пристроях мікро-наноелектроніки. Створення прототипів чутливих датчиків магнітного поля.
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