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In the present work, we analyze acousto-optic (AO) interactions between acoustic waves (AW) and circularly polarized optical eigenwaves in gyrotropic crystals. We find that the AO diffraction of circularly polarized eigenwaves can be divided into six different interaction types. Contrary to the AO interactions analyzed earlier for the case of linearly polarized optical eigenwaves, we distinguish three isotropic interaction types and three anisotropic ones. Moreover, unlike the isotropic AO interactions of linearly polarized eigenwaves of n o - n o and n e - n e interaction types, the effective elasto-optic coefficient (EEC) in the case of interactions between circularly polarized eigenwaves does not depend on the sign of an incident circular optical wave. The anisotropy of the EEC and AO figure of merit is analyzed for a particular case of lead germanate crystals, P b 5 G e 3 O 11 . We demonstrate that the maximal AO figures of merit are achieved for type I isotropic diffraction at the quasi-longitudinal AW. Our calculations are confirmed by the experimental data obtained for the EEC using the Dixon–Cohen method. The experiment is concerned with the AO interactions of circular eigenwaves in P b 5 G e 3 O 11 .

We determine full matrices of piezo-optic and elasto-optic coefficients for lead germanate crystals, P b 5 G e 3 O 11 , using Dixon–Cohen and interferometric methods. Two different types of samples are studied, single- and multi-domain. We show that the correct data for the P b 5 G e 3 O 11 crystals can be obtained only with single-domain samples, since the domain structure induces a number of features that make the final results unreliable. We demonstrate that the acousto-optic figures of merit reach high-enough values at the isotropic acousto-optic interactions with longitudinal acoustic waves propagating along the principal x and z axes ( 63 × 10 − 15 and 37 × 10 − 15 s 3 / k g ), respectively. At the same time, the efficiency of the acousto-optic interactions with transverse acoustic waves is low. The same is true concerning anisotropic acousto-optic diffraction, since the appropriate elasto-optic coefficients are small enough.

We report the results of comprehensive studies of the piezo-optic and elasto-optic effects in lithium tetraborate crystals, Li2B4O7. The full matrices of piezo-optic and elasto-optic coefficients are obtained using a recently developed method based on four-point bending. On this basis, we have estimated the acousto-optic figure of merit for Li2B4O7.

We analyze the effect of acoustic wave (AW) polarization states deviation from purely longitudinal and transverse on the anisotropy of the acousto-optic (AO) figure of merit for the case of AO interactions occurring in the principal crystallographic planes. In particular, we obtain phenomenological relations that describe the effective elasto-optic coefficient for the six types of AO interactions, which exhaust all of the possible isotropic AO diffractions. These relations are compared for the alternative cases when the deviations of polarization of the AWs from purely longitudinal and transverse ones are either taken into consideration or completely neglected. Our analysis carried out on the example of Tl3AsS4 crystals reveals that the deviation of AW polarization from its pure states influences the anisotropy of the AO figure of merit only when the AO interactions with quasi-transverse AWs are dealt with. This fact is caused by the peculiar acoustic and elasto-optic properties of Tl3AsS4. On the other hand, the situation can become different for other crystalline materials, where the angular dependences of the AO figure of merit can differ significantly in cases in which the deviation angle increases. This holds true for the AO interactions with both quasi-transverse and quasi-longitudinal AWs. Under these conditions, non-orthogonality of the AWs (or deviation from their longitudinal polarization states) affects essentially the AO characteristics. Finally, we determine the geometries of AO interactions for which the highest AO figures of merit are reached for the Tl3AsS4 crystals.

Complete matrices of piezo-optic and elasto-optic tensors are experimentally determined for Tl3AsS4 crystals. It is revealed that the piezo-optic coefficients are very high, ∼10-11 N/m2 in the order of magnitude. This implies that Tl3AsS4 can be referred to the best piezo-optic materials. The same concerns the elasto-optic coefficients, of which absolute values are in the interval 0.28-0.54. It is also found that, at the anisotropic and isotropic interactions with the slowest transverse and longitudinal acoustic waves, the acousto-optic figure of merit reaches extremely high values (1.99×10-12 s3/kg and 9.45×10-13 s3/kg, respectively). In other words, the Tl3AsS4 crystals can be referred to as one of the best acousto-optic materials for the visible and infrared spectral ranges.

In this paper the acoustic, elastic, piezooptic, photoelastic and acoustooptic properties of SrB 4 O 7 and PbB 4 O 7 crystals have been studied and thoroughly analyzed. The complete matrices of the corresponding coefficients have been obtained. The acoustooptic diffraction in PbB 4 O 7 crystals has been observed.

The results of studies for the refractive indices dispersion, optical activity, electro- and piezooptic effects, electrogyration effect, thermal expansion and ultrasonic wave velocities in organic-inorganic [(CH 2 OH) 3 CNH 3 )]H 2 PO 4 crystals are presented. The coefficients describing those effects are determined. It is found that [(CH 2 OH) 3 CNH 3 )]H 2 PO 4 crystals are characterized by a high electrooptic figure of merit.

The piezooptical (PO) parameters of the ferroelectric crystal Sn 2 P 2 S 6 with monoclinic symmetry are measured by an interferometric technique for the mechanical stress applied parallel to the three main crystallographic axes at light wavelength λ = 632.8 nm and room temperature (T = 293 K). Nine independent PO coefficients are determined experimentally. They exhibit quite large values: the largest measured component is π 11 = 15.6 pm N. The high PO coefficients presume potential applications of Sn 2 P 2 S 6 as high-efficient acousto-optic material.

We present comprehensive experimental measurements and analysis of anisotropy of the acoustic wave velocities for TI(3)AsS(4) crystals, including the obliquity and nonorthogonality of the acoustic waves, and the deviations from purely longitudinal and transverse polarization types. We have found that the crystals under analysis are characterized by rather low transverse wave velocities v(23) and v(32), which are both equal to 630 m/s. It is shown that the efficiency of acoustooptic (AO) interactions in TI(3)AsS(4) can be notably increased when providing anisotropic interaction with the slowest transverse acoustic wave. Under the previously mentioned conditions, the AO figure-of-merit can be estimated to be extremely high, i.e., approximately 3×10(-12) s(3)/kg.

Photoelastic coefficients of beta-BaB2O4 and Li2B4O7 crystals are calculated on the basis of piezooptic measurements performed with interferometric technique and the elastic compliance and stiffness data. Using the experimental results, the acoustooptic (AO) figure of merit (FM) has been estimated for the possible geometries of AO interaction. It is shown that the AO FM for the ABO and LTB crystals reach respectively the values M2=243.4*10-15s3/kg and M2=2.57*10-15s3/kg, if the interaction with the slowest ultrasonic waves (v=933.5m/s and v=3173m/s) is concerned. The directions of propagation and polarization of those acoustic waves are obtained on the basis of construction of indicative surfaces of the acoustic wave velocities.

The optical (refractive indices, piezooptic coefficients, optical damage thresholds and the transmission spectra) and the elastic properties of the borate crystals (BaB2O4, Li2B4O7 and CsLiB6O10) are investigated. The results of measurements for the velocity of longitudinal and transverse ultrasonic waves of the borate crystals are presented. The components of the elastic matrix Cmn of these crystals are calculated on the basis of the ultrasonic velocity measurements. Using the determined values of the refractive, elastic and elastooptic tensor components, we have calculated the largest values of the acoustooptic figure of merit M2.

For the first time, to the best of our knowledge, we have experimentally determined all of the components of the piezo-optic tensor for monoclinic crystals. This has been implemented on a specific example of triglycine sulfate crystals. Based on the results obtained, the complete elasto-optic tensor has been calculated. Acousto-optic figures of merit (AOFMs) have been estimated for the case of acousto-optic interaction occurring in the principal planes of the optical indicatrix ellipsoid and for geometries in which the highest elasto-optic coefficients are involved as effective parameters. It has been found that the highest AOFM value is equal to 6.8×10−15 s3/kg for the case of isotropic acousto-optic interaction with quasi-longitudinal acoustic waves in the principal planes. This AOFM is higher than the corresponding values typical for canonic acousto-optic materials, which are transparent in the deep ultraviolet spectral range.

We have analyzed the anisotropy of acoustooptic figure of merit M2 for KH2PO4 crystals. Basing on our results, the highest M2...

We develop a technique for analyzing the anisotropy of an acousto-optic figure of merit for crystals belonging to tetragonal symmetry groups 4/m, 4, and 4¯. The technique is based on phenomenological relations that describe anisotropies of the effective elasto-optic coefficients and the acoustic wave velocities. Our approach is verified on the example of NaBi(MoO4)2 crystals for all possible types and geometries of acousto-optic interactions. We list and characterize the acousto-optic interaction geometries at which the maximal acousto-optic figures of merit are reached for both isotropic and anisotropic interaction types. Finally, we show that the acousto-optic efficiency of NaBi(MoO4)2 originates mainly from large elasto-optic coefficients.

Interaction of acoustic and light waves with accounting for elastooptic and elastogyration effects is theoretically described. Collinear acoustogyration diffraction in quartz and paratellurite crystals is experimentally investigated and thoroughly analyzed. Piezogyration effect is experimentally studied for TeO2 crystals. The acoustogyration efficiency and the acoustogyration figure of merit calculated for a number of crystals (GaAs, TeO2 and SiO2) are shown to be too small for experimental detection. On the other hand, we demonstrate that the light diffraction at periodical distribution of the imaginary part of dielectric permittivity related to the piezogyration effect should, in principle, be observed for the case of interaction of optical waves with enantiomorphous ferroelastic domain structure and in cholesteric liquid crystals.

Piezooptic coefficients of Sn2P2S6 crystals are experimentally determined for and with the aid of interferometric technique. The components of the elastic stiffness tensor for these crystals are calculated on the basis of studies for the acoustic wave velocities. It is shown that estimated acoustooptic figure of merit can achieve extremely high values for Sn2P2S6 crystals.

We have shown that the maximal acoustooptic figure of merit for the collinear type of acoustooptic diffraction in LiNbO3 crystals is...

We have analyzed the anisotropy of acousto-optic figure of merit (AOFM) in LiNbO3 crystals for the three different types of...

In this work we present the results of comprehensive studies of the piezo-optic and elasto-optic effects in NaBi(MoO4)2 crystals. The full matrices of the piezo-optic and elasto-optic coefficients for the NaBi(MoO4)2 crystals are obtained for the first time, to the best of our knowledge. The acousto-optic effect in the NaBi(MoO4)2 is analyzed for the case of interactions of optical waves with the slowest acoustic waves. It is shown that the crystals under analysis can be efficiently used as working elements for the collinear acousto-optic tunable filters.

Basing on the comprehensive studies of acoustic properties for NaBi(MoO4)2 crystals, we have determined the full matrices of elastic stiffness...

We have determined experimentally the acoustic wave velocities for Pb2P2Se6 crystals and obtained complete matrices of the elastic stiffness and elastic compliance coefficients on this basis. The anisotropy of the acoustic wave velocities has been analyzed, and the spatial directions of propagation and polarization of the slowest acoustic waves have been determined. In the case of acousto-optic (AO) interaction with these waves, the AO figure of merit can reach extremely high values, thus making Pb2P2Se6 a promising AO material for the infrared spectral range.

Electrooptic coefficient of CsLiB6O10 crystals has been experimentally determined as r63=3.3*10-12m/V. The half-wave voltage for CsLiB6O10 (Ul/2=26 kV) is three orders of magnitude larger than that of the known KDP crystals.

We have revealed a large Faraday rotation in tin thiohypodiphosphate (Sn(2)P(2)S(6)) crystals, which makes this material promising for magneto-optics. The effective Faraday tensor component and the Verdet constant for the direction of the optic axis have been determined by measuring the pure Faraday rotation in Sn(2)P(2)S(6) crystals with both the single-ray and small-angular polarimetric methods at the normal conditions and a wavelength of 632.8 nm. The effective Verdet constant is found to be equal to 115 rad/T x m.

We have studied the acoustooptic (AO) diffraction in Sn2P2S6 crystals and found that they manifest high values of AO figure of merit. The above crystals may therefore be used as highly efficient materials in different AO applications., Comment: 5 pages, 1 figure

We have determined ten piezooptic tensor components for monoclinic triglycine sulfate crystals, using an interferometric method. Acoustooptic figure of merit has been...

Anisotropies of the acoustooptic figure of merit (AOFM) and the effective elastooptic coefficient under the conditions of collinear diffraction have...

We address the errors found in our recent analysis of anisotropy of the acoustooptic figure of merit in TeO2 crystals...

We suggest a new approach for ranking Ukrainian scientific journals and proceedings. According to a number of criteria, all the journals...