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About the Possibility of Linearization of Quadratic Cotton-Mouton Birefringence Change due to <IB>kH<D>-Effect. Про можливості лінеаризації квадратичної магнітооптичної Котон-Мотонівської зміни двозаломлення за рахунок <IB>kH<D>-ефекту
Пошуковий запит: (<.>I=Ж42080<.>)
Загальна кількість знайдених документів : 121
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Vlokh, R.

About the Possibility of Linearization of Quadratic Cotton-Mouton Birefringence Change due to kH-Effect. Про можливості лінеаризації квадратичної магнітооптичної Котон-Мотонівської зміни двозаломлення за рахунок kH-ефекту. - ISSN 1609-1833


A possibility for appearance of the so-called kH-effect in crystals is analyzed, which originates from the light absorption, spatial dispersion and the influence of magnetic field. It is shown that the kH-effect can lead to linearization of the Cotton-Mouton effect. The coefficients of both the Cotton-Mouton (<$E(n sub 3 sup 3 beta sub 31 ~-~n sub 1 sup 3 beta sub 11 )~=~2,8~ times ~10 sup -15 ~ roman Oe sup -2}) and the kH-effect ( <$Edelta sub 1112 ~ symbol Г ~0,72~ times ~10 sup -20 ~ roman {m"/"Oe}>) are obtained for CdS crystals.



НАДХОДЖЕННЯ:
Acoustooptic Diffraction and Light Absorption in <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl) Crystals=Акустооптична дифракція та поглинання світла у кристалах <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl).

Martynyuk-Lototska, I.

Acoustooptic Diffraction and Light Absorption in <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl) Crystals=Акустооптична дифракція та поглинання світла у кристалах <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl).. - ISSN 1609-1833


The acoustooptic (AO) efficiency of <$Eroman {Cs sub 2 HgBr sub 4 ,~Cs sub 2 HgCl sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> crystals is experimentally studied. It is shown that <$Eroman {Cs sub 2 HgBr sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> crystals are quite good AO materials. From the results for the absorption coefficients of <$Eroman {Cs sub 2 HgBr sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> it follows that the latter crystals are transparent in a wide spectral range (up to the light wavelength of <$E25~ mu roman m>). The AO efficiency value for <$Eroman {Cs sub 2 HgCl sub 4 }> crystal reaches <$Eeta ~=~40~%> at the power P = 4W of electric drive signal of piezoelectric transducer.



НАДХОДЖЕННЯ:
Acoustooptic Diffraction in Borate Crystals

Martynyuk-Lototska, I.

Acoustooptic Diffraction in Borate Crystals. - ISSN 1609-1833


The efficiency of acoustooptic (AO) diffraction in (<$Ealpha - roman {BaB sub 2 O sub 4 }> and <$Eroman {Li sub 2 B sub 4 O sub 7 }> crystals is studied experimentally. The crystals are shown to be quite good AO materials. The efficiency of AO diffraction in (<$Ealpha - roman {BaB sub 2 O sub 4 }> reaches (=30 % at the electric signal power of P = 0,7W for the transverse acoustic wave and 15 % at the power of P = 0,56W for the longitudinal wave. The same parameter for <$Eroman {Li sub 2 B sub 4 O sub 7 }> reaches <$Eeta ~=~21~%> at P = 0,81W for the longitudinal acoustic wave.



НАДХОДЖЕННЯ:
Acoustooptic Interaction in Barium Beta-Borate Crystals

Martynyuk-Lototska, I.

Acoustooptic Interaction in Barium Beta-Borate Crystals. - ISSN 1609-1833


Basing on the measurements of photoelastic coefficients, acoustic waves velocities and the refractive indices, the possible geometries for acoustooptic interaction in <$Ebeta - roman {BaB sub 2 O sub 4 }> crystals have been analysed. It has been shown that the acoustooptic figureof merit achieves its maximum value when the transverse acoustic wave v13 with the velocity 817 m/s is propagated in YZ-plane. In this case <$EM sub 2 ~=~95,35~ times ~10 sup -15 ~ roman {s sup 3"/"kg}>.



НАДХОДЖЕННЯ:
Analysis of Singularity Properties of the Radiation Field in Low-Mode Optical Fibres

Alexeyev, A. N.

Analysis of Singularity Properties of the Radiation Field in Low-Mode Optical Fibres. - ISSN 1609-1833


We analyze the physical processes in optical fibres on the basis of the radiation field emitted from the output end. It is demonstrated that one can judge about the excitation coefficients of the guided modes in ideal optical fibres from the position of singularity point and equal intensity lines. We have obtained dependence of the excitation coefficients of guided optical vortices (OV) upon the displacement of the OV incident on the input fibre end. It is shown that the motion of the singularity point at the output end is caused by the rotational Doppler effect.



НАДХОДЖЕННЯ:
Angular Momentum of Electromagnetic Field in Areas of Polarization Singularities

Mokhun, I.

Angular Momentum of Electromagnetic Field in Areas of Polarization Singularities. - ISSN 1609-1833


It is shown that physical manifestations of any optical singularity are, in one way or another, related to a specific temporal behaviour of the field, no matter scalar or vector cases are realized. Polarization singularities of the vector field are associated with a presence or absence of angular momentum of electromagnetic field. In the vicinity of C - point the orbital angular momentum is observed if the sings of topological charge of the vibration phase and the handedness factor are different.



НАДХОДЖЕННЯ:
Anisotropy of Laser-Induced Bulk Damage of Single Crystals

Krupych, O.

Anisotropy of Laser-Induced Bulk Damage of Single Crystals. - ISSN 1609-1833


The regularities of laser-induced damage of anisotropic materials, such as <$Eroman LiNbO sub 3> and KDP dielectric single crystals, are experimentally studied. It is revealed that the shape of laser-induced damage in the dielectric crystals depends on the elastic symmetry of crystal and the propagation direction of the laser beam. When the beam propagates along the optic axis of crystals, the figures of the laser damage are six-path stars for <$Eroman LiNbO sub 3> and four-path ones for KDP crystals. For the direction parallel to X and Y axes in KDP crystal, the damage has initially cross-like configuration, with further splitting of Z-oriented crack into two cracks in the process of damage evolution, leading to transformation of orthogonal-type damage to a hexagonal-type one.



НАДХОДЖЕННЯ:
Appearance of Optical Vortex at Conical Refraction. Examples of <$Eroman bold {NaNO sub 2 }> and <$Eroman bold {YFeO sub 3 }> Crystals

Vlokh, R.

Appearance of Optical Vortex at Conical Refraction. Examples of <$Eroman bold {NaNO sub 2 }> and <$Eroman bold {YFeO sub 3 }> Crystals. - ISSN 1609-1833


In the present paper it is shown that effect of conical refraction is accompanied by a generation of vortex due to the existing singularities on the surfaces of phase and group velocities in biaxial crystals. This fact is confirmed experimentally by the studies of conical refraction in <$Eroman YFeO sub 3> and interference patterns in <$Eroman NaNO sub 2> crystals. The angle of external conical refraction in <$Eroman YFeO sub 3> crystals determined by us is equal to <$E4,2 symbol Р>.



НАДХОДЖЕННЯ:
Application of Small-Angular Magnetooptic Polarimetry for Study of Magnetogyration in <$Eroman bold {(Ga sub 0,3 In sub 0,7 ) sub 2 Se sub 3 }> and <$Eroman bold {SiO sub 2 }> Crystals

Krupych, O.

Application of Small-Angular Magnetooptic Polarimetry for Study of Magnetogyration in <$Eroman bold {(Ga sub 0,3 In sub 0,7 ) sub 2 Se sub 3 }> and <$Eroman bold {SiO sub 2 }> Crystals. - ISSN 1609-1833


We present the results of studies for magnetogyration (MG) effect in <$Eroman {(Ga sub 0,3 In 0,7 ) sub 2 Se sub 3 }> and <$Eroman SiO sub 2> crystals performed with the small-angular polarimetric mapping technique. It is shown that the MG effect magnitude is comparable with the experimental error.



НАДХОДЖЕННЯ:
Baric Changes in the Optical Indicatrix of TGS Crystals with L-threonine Admixture

Kardash, V.

Baric Changes in the Optical Indicatrix of TGS Crystals with L-threonine Admixture. - ISSN 1609-1833


The influence of uniaxial mechanical stresses, applied along the principal crystal-physical axes, on the principal values of birefringence Дni is studied for TGS crystals with 5 % L-threonine admixture. It is revealed that <$EDELTA n sub i> are quite sensitive to themechanical stresses. The baric coefficients <$Edel roman {T sub c } "/" del sigma sub { roman m }> for the phase transition temperature appear to be less than those for the pure TGS. Temperature dependences and dispersion of the piezooptic coefficients are calculated. The jump-like changes in all of the piezooptic coefficients occurring at the Curie temperature in the doped crystals are explained with the contributions of a secondary electrooptic effect.



НАДХОДЖЕННЯ:
Cavity Mirrors for He-Ne Lasers with Simultaneous Lasing at the Transitions with <$Ebold { lambda sub 0 ~=~0,6328~ mu roman m}> and <$Ebold { lambda sub 1 ~=~3,39~ mu roman m}>=Резонаторні дзеркала для He-Ne лазера з одночасною генерацією на переходах з <$Ebold { lambda sub 0 ~=~0,6328~ roman мкм}> і <$Ebold { lambda sub 1 ~=~3,39~ roman мкм}>

Bondarchuk, Ya. M.

Cavity Mirrors for He-Ne Lasers with Simultaneous Lasing at the Transitions with <$Ebold { lambda sub 0 ~=~0,6328~ mu roman m}> and <$Ebold { lambda sub 1 ~=~3,39~ mu roman m}>=Резонаторні дзеркала для He-Ne лазера з одночасною генерацією на переходах з <$Ebold { lambda sub 0 ~=~0,6328~ roman мкм}> і <$Ebold { lambda sub 1 ~=~3,39~ roman мкм}>. - ISSN 1609-1833


In this work the approach to designing and manufacturing the mirrors for optical cavities of the lasers with simultaneous generation at two different transitions is formulated. Using the model of equivalent layer, the structures of the mirrors for He-Ne lasers operating at the wavelengths of <$Elambda sub 0 ~=~0,6328~ mu roman m> and <$Elambda sub 1 ~=~3,39~ mu roman m> are described. The efficiency of use of the obtained mirrors in serial lasers is demonstrated.



НАДХОДЖЕННЯ:
Change of Optical Properties of Space under Gravitation Field

Vlokh, R.

Change of Optical Properties of Space under Gravitation Field. - ISSN 1609-1833


It is shown that, in the model of a flat 3D space, the time (i.e., the Hubble or the gravitation constant) plays a role of a spatial property. Gravitation field of spherical central mass does not lead to a lowering of symmetry of the space and appearance of anisotropy. In particular, the relations that describe the changes in the refractive indices of the space treated as an optical medium near the massive spherical body under the influence of its gravitation field have been derived.



НАДХОДЖЕННЯ:
Combined Piezoelectrooptic Effect in Rochelle Salt at the Phase Transition

Vlokh, R.

Combined Piezoelectrooptic Effect in Rochelle Salt at the Phase Transition. - ISSN 1609-1833


The results of study of piezoelectrooptic (PEO) effect in the course of ferroelectric-ferroelastic phase transition in Rochelle salt crystals are presented. The coefficient of the combined effect is obtained from measurements of the changes in the electrooptic coefficients under the action of mechanical stress and the changes in the piezooptic coefficients under the action of electric field (or spontaneous polarization). It is shown experimentally that the values of both coefficients are the same, aspredicted by the theory. The temperature dependence of the coefficient of combined PEO effect is obtained. Its anomalous behaviour at the phase transition appears due to the dielectric permitivity anomaly. It is also demonstrated that the change in the piezooptic coefficients at the phase transition in Rochelle salt crystals may be satisfactorily explained as a result of linear and quadratic PEO effect induced by spontaneous polarization.



НАДХОДЖЕННЯ:
Comment on "Effective Refractive Index Tensor for Weak-Field Gravity" by P. Boonserm, C. Cattoen, T. Faber, M. Visser and S. Weinfurtner

Vlokh, R. O.

Comment on "Effective Refractive Index Tensor for Weak-Field Gravity" by P. Boonserm, C. Cattoen, T. Faber, M. Visser and S. Weinfurtner. - ISSN 1609-1833


P. Boonserm et. al have tried to describe some anisotropic optical effects in the gravitation field in frame of the general relativity and by introducing the so-called "effective refractive index tensor" similarly to anisotropic crystals. We suppose that this approach is inconsequent because of the following: if one develops this claim, it would be necessary to attribute the gravitation field to the properties of matter, including its electric properties, the refractive index is not a tensorial quantity and the analogy to the situation in anisotropic crystals does not lead to artificial "effective refractive index tensor" but to naturally introduced tensor of optical-frequency dielectric impermeability of matter.



НАДХОДЖЕННЯ:
Comparison of the Blood Component Optical Transmission Spectra of White Rats with and without Ethanol Intoxication

Dudok, T.

Comparison of the Blood Component Optical Transmission Spectra of White Rats with and without Ethanol Intoxication. - ISSN 1609-1833


In this report we present spectroscopic transmission studies of hemoglobin extracted from the vein blood of laboratory rats free of and exposed to ethanol intoxication, which are performed in order to analyze the relevant spectral differences. The animals were divided into the intoxicated group (IG) and the control group (CG). The results show a noticeable difference of the absorption/transmission spectra of hemoglobin extracted from the blood of these two groups. The difference in the absorption spectra is probably associated with the fact that the vein blood of ethanol-intoxicated animals includes more RHb than that of the CG. The deoxygenation process rate for the hemoglobin of intoxicated animals reaches a higher value and is quicker than that for the CG. It means that the affinity of the IG hemoglobin to oxygen is smaller than that for the CG. The minimum in the transmission spectra of hemoglobin with the dissolved cibacron blue colouring agent is shifted to a longer wavelength range (620 nm).The transmittance value for the IG is smaller than that for the CG, implying probably that the immunoglobulin G (IgG) in the IG possesses a more essential decomposition of its spatial structure, when compare with the CG. The changes in the transmission spectra of hemoglobin are detected after adding <$Eroman {H sub 2 O sub 2 }> and bromthymol blue, indicating the protein conformational changes for the IG animals.



НАДХОДЖЕННЯ:
Complex Degree of Mutual Polarization of Biotissue's Speckle-Images

Ushenko, Ye. G.

Complex Degree of Mutual Polarization of Biotissue's Speckle-Images. - ISSN 1609-1833


The article is directed to studies for the statistics of coordinate distributions of the complex degree of mutual polarization (CDMP) characterising biotissues' images. Diagnostic possibilities of the 2D distributions of the images' CDMP correspondingto physiologically normal and degeneratively-dystrophically changed biological tissues are analysed.



НАДХОДЖЕННЯ:
Conjugated Polyaminoarenes as Electrochromic Layers for Non-Emissive Displays

Aksimentyeva, O.

Conjugated Polyaminoarenes as Electrochromic Layers for Non-Emissive Displays. - ISSN 1609-1833


Electrochromic properties of polyaminoarenes with different molecular structure, such as poly-o-aminophenol (POAP), poly-o-toluidine (POTI), poly-o-methoxyaniline (POMA) and polyaniline (PANI), are studied as potential materials for the three- and two-electrode construction of electrochromic devices.



НАДХОДЖЕННЯ:
Conoscopic Patterns for Optically Uniaxial Gyrotropic Crystals in the Vicinity of Isotropic Point

Vasylkiv, Y.

Conoscopic Patterns for Optically Uniaxial Gyrotropic Crystals in the Vicinity of Isotropic Point. - ISSN 1609-1833


We have presented computer simulations of conoscopic patterns occurring in optically uniaxial gyrotropic crystals in the vicinity of isotropic point for a number of sets of crystal parameters and orientations. The appearance of special directions characterized by equalization of linear and circular birefringences has been revealed.



НАДХОДЖЕННЯ:
Correlation- and singular-optical approaches in diagnostics of polarization inhomogeneity of coherent optical fields from biological tissues

Angelsky, O. V.

Correlation- and singular-optical approaches in diagnostics of polarization inhomogeneity of coherent optical fields from biological tissues. - ISSN 1609-1833


The paper presents results related to the correlation structure of polarization images of biological tissues. The technique for measuring coordinate distribution of the degree of mutual polarization has been proposed. The topological (singular) description of polarization-inhomogeneous images of biological tissues has been analyzed. It has been shown that the average statistical size of the S-contour correlates with the half-width of autocorrelation function for the coordinate distribution of the mutual polarization degree.



НАДХОДЖЕННЯ:
Crystal Optical Properties of Inhomogeneous Plates and the Problems of Polarization Tomography of Photoelastic Materials

Kushnir, O.

Crystal Optical Properties of Inhomogeneous Plates and the Problems of Polarization Tomography of Photoelastic Materials. - ISSN 1609-1833


Using the Jones matrix formalism, crystal optical properties of inhomogeneous material consisting of a pile of weakly birefringent plates are analysed in relation to the cell model adopted in polarization tomography of 3D dielectric tensor field in photoelastic media. It is shown that the material manifests in general an "apparent" optical gyration caused by different orientations of the plates. Relations between the polarimetric parameters and the dielectric tensor components are ascertained for thecase of weak optical anisotropy.



НАДХОДЖЕННЯ:
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