The second harmonic spectrum of ${\mathrm{Cr}}_{2}$${\mathrm{O}}_{3}$ is studied in the 1.7-2.9 eV spectral range as a function temperature. Below N\'eel temperature ${T}_{N}=307.5$ K nonlinear electric susceptibility ${\ensuremath{\chi}}_{\mathrm{ijk}}^{e}(c)$ appears, which changes sign under time-reversal operation. interference this with time-invariant magnetic ${\ensuremath{\chi}}_{\mathrm{ijk}}^{m}(i)$ leads to pronounced polarization dependence for circularly polarized light...

The reflection of light from a medium with ordered spin structure characterized by the breakdown time-reversal and parity symmetry is expected to be non-reciprocal even if net magnetic moment equals zero. We report on first experimental observation spontaneous rotation circular dichroism in magnetoelectric Cr2O3. Non-reciprocal effects were observed below antiferromagnetic transition temperature TN=307 K their behaviour roughly corresponds that order parameter. Observed values (1-4)*10-4 for...

Pulsed laser deposition has been used to grow thin (10–84 nm) epitaxial layers of Yttrium Iron Garnet Y3Fe5O12 (YIG) on (111)–oriented Gadolinium Gallium substrates at different growth conditions. Atomic force microscopy showed flat surface morphology both micrometer and nanometer scales. X-ray diffraction measurements revealed that the films are coherent with substrate in interface plane. The interplane distance [111] direction was found be by 1.2% larger than expected for YIG...

Optical effects due to electric dipole--magnetic dipole interference were predicted for crystals which are noninvariant under space-inversion and time-reversal symmetry. We report measurements of the nonreciprocal rotation ellipticity light reflected from antiferromagnetic-magnetoelectric C${\mathrm{r}}_{2}$${\mathrm{O}}_{3}$ in a spectral range 1.6 2.5 eV, comprises $^{4}A_{2}\ensuremath{\rightarrow}^{2}E$, $^{2}T_{1}$, $^{4}T_{2}$ transitions. An analysis provides new information about...

Thin (4-20 nm) yttrium iron garnet (Y3Fe5O12, YIG) layers have been grown on gadolinium gallium (Gd3Ga5O12, GGG) 111-oriented substrates by laser molecular beam epitaxy in 700-1000 °C growth temperature range. The were found to atomically flat step-and-terrace surface morphology with step height of 1.8 Å characteristic for YIG(111) surface. As the is increased from 700 1000 terraces become wider and gradually changes layer step-flow regime. Crystal structure studied electron X-ray...

Abstract Optical effects of the first and second order with respect to parameter (1 is antiferromagnetic vector) have been studied in Cr2O3 around its phase transition at TN = 306 K from paramagnetic state. The magnetic linear birefringence characterized by a rather large magnitude Δn sp ≃ 10−3 contribution fluctuations birefringence. study nonreciprocal optical rotation induced an electric field has shown that well defined first-order character. This result also supported observation...

The surface magnetic and structural properties of magnetite thin films have been probed by nonlinear second-harmonic generation optical method in high- (centrosymmetric, Oh) low- (noncentrosymmetric, C1) temperature phases. A model taking into account the cubic magnetocrystalline anisotropy symmetry reduction due to a magnetically modified layer is supposed describe azimuth variations response. metal-isolator transition (Verwey) manifests itself an increase response (∼25%) decrease contrast (∼50%).

Second-harmonic generation (SHG) at normal incidence in transmission geometry was studied Bi-containing magnetic garnet thin films on gadolinium-gallium (GGG) substrates of (111) and (210) types. A Q-switched Nd-YAG laser used as a radiation source. The intensity the SHG lower than that crystalline quartz but it nevertheless reliably detectable. study function rotation angle around their normals showed signal is well described by phenomenological expressions derived under assumption point...

Single crystals of 2-methylbenzimidazolium perchlorate were prepared for the first time with a slow evaporation method from an aqueous solution mixture 2-methylbenzimidazole (MBI) and perchloric acid HClO4. The crystal structure was determined by single X-ray diffraction (XRD) confirmed XRD powder. Angle-resolved polarized Raman Fourier-transform infrared (FTIR) absorption spectra consist lines caused molecular vibrations in MBI molecule ClO4− tetrahedron region ν = 200–3500 cm−1 lattice...

The magnetization dynamics of single-crystalline Fe(001) thin films with Cr cap layers has been studied by an all-optical time-resolved pump-probe technique. system is characterized a fourfold in-plane magnetic anisotropy. We observed long-lived $(\ensuremath{\sim}1\phantom{\rule{0.3em}{0ex}}\mathrm{ns})$ oscillations caused the ultrafast $(\ensuremath{\sim}0.15\phantom{\rule{0.3em}{0ex}}\mathrm{ps})$ optical pulse excitation. are associated temporal variation component ${M}_{z}$ normal to...

We have studied the magnetic field dependences of optical second harmonic generation (SHG) in MBE-grown $\mathrm{Fe}∕\mathrm{Cr}∕\mathrm{Fe}∕\mathrm{Ag}∕\mathrm{Ga}\mathrm{As}(100)$ heterostructures displaying both bilinear and biquadratic interlayer exchange coupling. The $\mathbf{H}$ was applied (100) surface plane along easy ([001]) hard ([110]) axes in-plane fourfold anisotropy. SHG has been measured reflection at near normal incidence for different polarization combinations...

Abstract Linear magnetoelectric effect (ME) in epitaxial iron garnet films of (YBiPrLu)3 (FeGa)5O12 composition has been studied by means optical polarimetric method with spatial resolution ∼2.5 μm. The measurements were carried out both longitudinal H∥E and transversal H⊤E geometry for grown on the substrates (111) (210)-orientation. magnitude ME within individual magnetic domain originated from wall movement is evaluated. strong anisotropy (210)-films was observed regime rotation...

Polycrystalline films of betaine phosphite (BPI) were grown by evaporation method on SiO2 and LiNbO3 substrates with interdigital transducers. Large (∼1 mm) single-crystalline blocks visualized in a polarizing microscope the reflection mode. Temperature dependences film capacity at frequencies 120 Hz–1 MHz exhibit strong maximum temperature ferroelectric phase transition BPI bulk crystals. The effect bias electric field was studied. variations dielectric permittivity are analyzed using...

Epitaxial layers of CoFeB were grown on MgO by means laser molecular beam epitaxy using $\mathrm{C}{\mathrm{o}}_{40}\mathrm{F}{\mathrm{e}}_{40}{\mathrm{B}}_{20}$ target. The growth was combined with in situ structural characterization three-dimensional reciprocal space mapping obtained from reflection high energy electron diffraction (RHEED) data. High-temperature single stage regime adopted to fabricate layers. As confirmed the atomic force microscopy, surface consists closely spaced...

We show that a magnetic field induces strong birefringence in noncentrosymmetric cubic crystals of ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ the Voigt configuration $\mathbf{k}\ensuremath{\perp}\mathbf{B}$. The induced can be separated into linear magnetospatial dispersion $\mathrm{kB}$ type, and quadratic ${B}^{2}$ type. effect is strikingly anisotropic, whereas fully isotropic. A microscopic theory proposed for explaining symmetric antisymmetric contributions to near...

The theoretical part of the research includes analysis symmetry properties and selection rules transitions. A detailed investigation is made for KNiF3 where exciton, exciton-magnon exciton-phonon transitions through Brillouin zone are found. Analysis also allows prediction shape intensity magnetic circular linear dichroisms (MCD MLD). Experimental study optical absorption dichroism in temperature range 6-300K. fine structure 3A2 to 1Ea connected with: (a) pure exciton their splitting by...

ABSTRACT Polycrystalline films of betaine phosphite (BPI) and triglycine sulphate (TGS) were grown by the evaporation method on different substrates (α-SiO2, α-Al2O3 LiNbO3 with interdigital transducers, Al/SiO2). Large (∼1 mm in BPI ∼0.2 TGS) single-crystalline blocks visualized a polarizing microscope reflection mode. Blocks are characterized preferable in-plane orientation ferroelectric axis. Temperature dependences TGS film capacity at frequencies 120 Hz–1 MHz exhibit strong maximum...

New single crystals, based on 2-methylbenzimidazole (MBI), of MBI-phosphite (C16H24N4O7P2), MBI-phosphate-1 (C16H24N4O9P2), and MBI-phosphate-2 (C8H16N2O9P2) were obtained by slow evaporation method from a mixture alcohol solution MBI crystals water phosphorous or phosphoric acids. Crystal structures chemical compositions determined crystal X-ray diffraction (XRD) analysis confirmed XRD powders elemental analysis. Raman spectroscopy new evidences the presence in MBI-, H3PO3-, H3PO4-...

We study molecular beam epitaxy growth, morphology, crystal structure, and magnetic properties of Co nanoislands on CaF${}_{2}$/Si(111) surface. In order to have a full appreciation complex growth kinetics at different stages, comprehensive CaF${}_{2}$ is carried out by atomic force, scanning electron, transmission electron microscopies in the direct space, as well x-ray diffraction reciprocal space. These experimental data are complemented theoretical modeling. Magnetic characterized...

Abstract Thin polycrystalline films of amino acid ferroelectrics glycine phosphite (GPI) have been prepared by evaporation method on NdGaO3(001) substrate with interdigital structure electrodes deposited the surface. Optical images obtained means polarized microscope in reflection mode shown that consist small single crystal blocks several tens microns size. X-ray diffraction analysis proves non-polar c* axis coincides normal to surface, and polar b is oriented film plane. Temperature...

A comparative analysis of crystal structure, Raman spectra, and dielectric hysteresis loops was carried out for organic ferroelectric crystals 2-methylbenzimidazole (MBI) grown from ethanol (MBIet), acetone (MBIac), deuterated (MBId-ac), or prepared by sublimation gas phase (MBIgas). spectroscopy shows identical frequencies molecular vibrations in all studied crystals, proving the same structure. At time, a detailed asymmetry powder XRD reflection profiles indicates presence nano-scaled...