共查询到20条相似文献,搜索用时 78 毫秒
1.
H.C. Pedersen P.M. Johansen D.J. Webb E.V. Podivilov 《Applied physics. B, Lasers and optics》1999,68(5):967-970
By using an alternative setup for photorefractive parametric oscillation in which wave mixing between the recording beams
is avoided it has become possible to make more detailed comparisons with the space-charge wave theory. In the present paper
we compare the experimental features of longitudinal parametric oscillation observed in a crystal of Bi12SiO20 with the theoretical predictions.
Received: 24 November 1998 / Revised version: 13 January 1999 / Published online: 7 April 1999 相似文献
2.
D.G. Papazoglou A.G. Apostolidis E.D. Vanidhis 《Applied physics. B, Lasers and optics》1997,65(4-5):499-503
12 TiO20. The first two can be measured by simple and classical methods, but the coexistence of optical activity, electrogyration,
field-induced linear birefringence, and piezoelectric and photoelastic effects in photorefractive materials such as Bi12TiO20 complicate the measurement of the electro-optic coefficient. For normal incidence of linearly polarized light we derive analytic
expressions for the polarization of light that has passed through the crystal. The ellipticity of the polarization is a function
of the electric-field-induced linear birefringence and hence of the electro-optic coefficient of the crystal. Therefore measurement
of the ellipticity as a function of an electric field externally applied to the crystal leads to an electro-optic coefficient
r41 of 5.3±0.1 pm/V.
Received: 22 December 1996/Revised version: 21 March 1997 相似文献
3.
G. Cedilnik M. Esselbach A. Kiessling R. Kowarschik E. Nippolainen A.A. Kamshilin V.V. Prokofiev 《Applied physics. B, Lasers and optics》1999,68(5):983-987
In a photorefractive Bi12SiO20 crystal with high applied electric ac field of square-wave shape a fast two-wave coupling response (less than 1 s) and a
slow hologram readout decay (minutes) was found for a wavelength of 633 nm. This can be explained by electron–hole transport
with two trap levels. An intensity dependence of the slower complementary grating was found. Illuminating with the readout
wave without applied electric field leads to a very slow grating decay (many hours).
Received: 18 November 1998 / Revised version: 3 February 1999 / Published online: 7 April 1999 相似文献
4.
N.C. Deliolanis A.G. Apostolidis E.D. Vanidhis D.G. Papazoglou 《Applied physics. B, Lasers and optics》2002,75(1):67-73
We study the influence of the application of an external electric field on the grating formed in (1-10) and (111)-cut photorefractive
sillenite crystals. Optimum conditions for application of the bias field are examined, taking into account the shift of the
grating orientation for maximum diffraction efficiency along the crystal depth. The contribution of the piezoelectric effect
is considered both in the electro-optic tensor and space charge field calculations. An analysis on the diffractive properties
under these optimum conditions shows an increase of 30% in maximum diffraction efficiency in Bi12GeO20, and experimental verification for this is provided.
Received: 5 November 2001 / Revised version: 18 April 2002 / Published online: 8 August 2002 相似文献
5.
E. Nippolainen V.V. Prokofiev A.A. Kamshilin T. Jaaskelainen 《Applied physics. B, Lasers and optics》1999,69(1):45-50
We present an experimental study of the self-pumped phase-conjugate-mirror (SPPCM) recording in a Bi12TiO20 sample due to the partial internal reflection of the pump beam from the rear face. SPPCM has been recorded under an external
alternating electric field of a square-wave form with response time equal to 170 s at the pump beam intensity of 520 mW/cm2. The mechanism of the SPPCM formation is similar to that of photorefractive double-phase-conjugate mirrors. The most effective
SPPCM is recorded at the much larger pump-beam-incident angle than it could be supposed from the typical angular dependence
of the two-wave-mixing gain factor. Strong dependence of the gain distribution on the pump-beam-propagation angle is observed.
It is found that the response time strongly depends on the preliminary history of the sample.
Received: 11 August 1998 / Revised version: 14 January 1999 / Published online: 28 April 1999 相似文献
6.
Honghao Xu Yuanyuan Zhang Huaijin Zhang Haohai Yu Zhongben Pan Yicheng Wang Shangqian Sun Jiyang Wang R.I. Boughton 《Optics Communications》2012,285(19):3961-3966
A Nd:Bi12SiO20 crystal was grown by the Czochralski method. The thermal properties of the crystal were systematically studied. The thermal expansion coefficient was measured to be α=11.42×10?6 K?1 over the temperature range of 295–775 K, and the specific heat and thermal diffusion coefficient were measured to be 0.243 Jg?1 k?1 and 0.584 mm2/s, respectively at 302 K. The density was measured to be 9.361 g/cm3 by the buoyancy method. The thermal conductivity of Nd:Bi12SiO20 was calculated to be 1.328 Wm?1 K?1 at room temperature (302 K). The refractive index of Nd:Bi12SiO20 was measured at room temperature at eight different wavelengths. The absorption and emission spectra were also measured at room temperature. Continuous-wave (CW) laser output of a Nd:Bi12SiO20 crystal pumped by a laser diode (LD) at 1071.5 nm was achieved with an output power of 65 mW. To our knowledge, this is the first time LD pumped laser output in this crystal has been obtained. These results show that Nd:Bi12SiO20 can serve as a laser crystal. 相似文献
7.
An analytical solution to the system of linear differential equations that describe the reconstruction of object wave using a transmission holographic grating formed in a cubic photorefractive piezoelectric (\(\left( {\overline {11} 0} \right)\))- cut crystal with the 23 symmetry is derived. The solution is used to interpret the experimental results on the dependence of the diffraction efficiency of mixed holograms on the thickness of the Bi12TiO20 crystal at a fixed orientation angle and three azimuths of linear polarization of the readout reference beam. The best agreement of the theoretical and experimental results on mixed holograms is reached when the inverse piezoelectric effect and photoelasticity are taken into account in addition to the conventional electrooptic effect. 相似文献
8.
N. V. Kukhtarev G. E. Dovgalenko V. N. Starkov 《Applied Physics A: Materials Science & Processing》1984,33(4):227-230
It is shown that dynamical hologram formation in photorefractive, optically active crystals is accompanied by polarization and energy exchange. These effects may be used like new effective holographic methods for determinations of crystal parameters and optical signal processing in real time. In self-diffraction a polarization rotation the order of degrees/cm for Bi12TiO20 and Bi12SiO20 is predicted. 相似文献
9.
N. Korneev D. Mayorga-Cruz J.J. Sánchez-Mondragón 《Applied physics. B, Lasers and optics》1999,68(5):859-862
The photoconductivity response time in Bi12SiO20 grows 3 orders of magnitude when the temperature changes from 350 to 200 K. We attribute this to the influence of shallow
traps with activation energy 0.4 eV. For low temperatures, the time of holographic grating formation is determined by the
time of shallow-level filling.
Received: 29 October 1998 / Revised version: 18 December 1998 / Published online: 12 April 1999 相似文献
10.
D.G. Papazoglou N.C. Deliolanis A.G. Apostolidis E.D. Vanidhis 《Applied physics. B, Lasers and optics》2000,71(6):841-848
We study the diffraction efficiency of volume phase gratings in Bi12GeO20, when the grating vector, lying on a (111) plane, is at an angle with respect to the crystallographic direction. An external
bias field parallel to the direction is applied during recording, thus, the recording conditions depend on the grating vector
orientation. The basic parameters determining the diffraction efficiency are the grating vector orientation, the rotatory
power and the field-induced linear birefringence (primary and secondary). Analytic expressions for the diffraction efficiency
have been obtained by taking into account all the above-mentioned parameters, provided that linearly polarized light is incident
on the crystal. In this configuration, the influence of the secondary electro-optic effect (inverse piezoelectric and photoelastic
effects) to the diffraction efficiency is actually stronger than the influence of the primary effect. Experimental results
are given.
Received: 3 January 2000 / Revised version: 6 June 2000 / Published online: 13 September 2000 相似文献
11.
V.M. Petrov S. Wevering M.P. Petrov E. Krätzig 《Applied physics. B, Lasers and optics》1999,68(1):73-76
12 GeO20, Bi12SiO20, Bi12TiO20).
Received: 17 June 1998/Revised version: 3 August 1998 相似文献
12.
A. T. Efremidis N. C. Deliolanis C. Manolikas E. D. Vanidhis 《Applied physics. B, Lasers and optics》2009,95(3):467-473
The photorefractive crystals of the sillenite family (Bi12SiO20 or BSO, Bi12GeO20 or BGO, and Bi12TiO20 or BTO) that belong to the cubic 23 point group are optically active, and exhibit the piezoelectric, elasto-optic, electro-optic
and electrogyration effect. In this paper we measure the dispersion of the electro-optic coefficient for all the crystals
of the sillenite family in the visible spectral range (500–800 nm). For this we measure by ellipsometry the polarization properties
of a beam transmitted in the transverse configuration under the action of an externally applied field. The experimental data
are fitted with an analytical expression of the beam polarization to find the electro-optic coefficient. The results show
a normal dispersion of the electro-optic coefficient in all three sillenite crystals, similarly to other electro-optic crystals. 相似文献
13.
14.
We report the measurement of the diffusion length, the Debye screening length and the quantum efficiency of photoelectron
generation in strongly light absorbing photorefractive Bi12TiO20 crystals, using fringe-locked running hologram experiments. The effective applied electric field inside the sample is also
computed and self-diffraction is considered. The novelty here, as compared to formerly reported experiments, is that the diffraction
efficiency is now measured simultaneously with the hologram speed v. From these data the above referred to photorefractive
and experimental parameters are obtained without the need for additional experiments. The method is used to analyze two photorefractive
Bi12TiO20 crystal samples, in different experimental conditions, using the 514.5 nm wavelength. The computed parameters are in good
agreement with the available information about these samples.
Received: 23 November 2000 / Published online: 21 March 2001 相似文献
15.
The large real-time hologram device made by the previous Bi12SiO20 single crystal wafer cutting method poses several problems such as a large residue of material hinders the practical use. A study was carried out to fabricate a real-time hologram device using inexpensive laterally cut circular (1 0 0) Bi12SiO20 single crystal wafers which would be suitable for practical use for 3-dimensional display. An angle incident on a (1 0 0) wafer is applicable to the real-time hologram. An optimal electrode design for a device with uniform diffraction efficiency was considered, and the device properties were experimentally investigated. 相似文献
16.
G. L. Messing S. Trolier-McKinstry E. M. Sabolsky C. Duran S. Kwon B. Brahmaroutu 《固体与材料科学评论》2004,29(2):45-96
Crystallographic texturing of polycrystalline ferroelectric ceramics offers a means of achieving significant enhancements in the piezoelectric response. Templated grain growth (TGG) enables the fabrication of textured ceramics with single crystal-like properties, as well as single crystals. In TGG, nucleation and growth of the desired crystal on aligned single crystal template particles results in an increased fraction of oriented material with heating. To facilitate alignment during forming, template particles must be anisometric in shape. To serve as the preferred sites for epitaxy and subsequent oriented growth of the matrix, the template particles need to be single crystal and chemically stable up to the growth temperature. Besides templating the growth process, the template particles may also serve as seed sites for phase formation of a reactive matrix. This process, referred to as Reactive TGG (RTGG), has been used to obtain highly oriented Pb(Mg1/3Nb2/3)O3-PbTiO3, Sr0.53Ba0.47Nb2O6, and (Na1/2Bi1/2)TiO3-BaTiO3. Highly oriented Bi4Ti3O12, Sr2Nb2O7, CaBi4Ti4O15, Pb(Mg1/3Nb2/3)O3-PbTiO3, Sr0.53Ba0.47Nb2O6 and (Na1/2Bi1/2)TiO3-BaTiO3 ceramics have been produced by TGG. The resulting ceramics show texture levels up to 90%, and significant enhancements in the piezoelectric properties relative to randomly oriented ceramics with comparable densities. For example, piezoelectric coefficients of textured piezoelectrics are from 2 to 3 times higher than polycrystalline ceramics and as high as 90% of the single crystal values. In textured PMN-PT, a low field (< 5 kV/cm) piezoelectric coefficient (d 33) of ~1600 pC/N was obtained with > 0.3% strain (at 50 kV/cm). The high field dielectric and electromechanical properties of textured perovskites are more hysteretic than those of single crystals, probably as a result of clamping by the residual template particles, residual random grains, the presence of non-ferroelectric second phases, and a wide orientation distribution. Lateral clamping of one grain by another may also be an important factor in fiber-textured samples. Means to further improve the quality of texture and thus properties of textured piezoelectric ceramics by TGG are presented. 相似文献
17.
V. I. Anisimkin 《Acoustical Physics》2016,62(2):165-168
The orientation dependences of the phase velocity, the effective electromechanical coupling coefficient, and the angle between the wave normal and the energy flux vector are numerically calculated for zeroand first-order Lamb waves propagating in the (001) basal plane of a Bi12SiO20 cubic piezoelectric crystal. It is shown that the anisotropies of these modes are different and depend on the plate thickness h and the wavelength λ. For h/λ < 1, the mode anisotropy can exceed the anisotropy of the corresponding characteristics of surface acoustic waves propagating in the same plane; for h/λ > 1, it approximately coincides with the SAW anisotropy for all the characteristics. 相似文献
18.
Zhihang Peng Dongxu Yan Qiang Chen Deqiong Xin Dan Liu Dingquan Xiao Jianguo Zhu 《Current Applied Physics》2014,14(12):1861-1866
Aurivillius phase Bi3Ti1−xTaxNb1−xWxO12 high temperature piezoceramics were prepared by a conventional solid state reaction method. The crystal structure, dielectric, electrical conduction and piezoelectric properties were systematically studied. Pure or modified Bi3TiNbO9 ceramics revealed the presence of only two-layered Aurivillius phase, indicating that Ta/W doping entered into the B-site of pseudo-perovskite structure and formed solid solutions. The Curie temperature had a strong reliance on the structural distortion. Furthermore, Ta/W dopants act as a donor doping, decrease the number of oxygen vacancies and facilitate the domain wall motion. As a result, Ta/W modifications significantly increase the DC resistivity and piezoelectric properties. Bi3Ti0.98Ta0.02Nb0.98W0.02O12 ceramics possess the optimum d33 value (∼12.5 pC/N) together with a high TC point (∼893 °C). Moreover, the resonance–antiresonance spectra demonstrate that the Ta/W-BTN ceramics are indeed piezoelectric in nature at 600 °C. The d33 value of BTTNW-2 ceramic remains ∼12.2 pC/N after annealing at 700 °C. These factors suggest that the BTTNW-based ceramic is a promising candidate for ultra-high temperature sensor applications. 相似文献
19.
A. A. Kamshilin V. V. Prokofiev R. Silvennoinen T. Jaaskelainen 《Optical and Quantum Electronics》1994,26(4):379-385
Experimental results for two-wave mixing experiments in a single Bi12TiO20 fibre-type crystal at a wavelength of 632.8 nm under transverse a.c. electric field are reported. An exponential gain factor =4.7 cm-1, which is much higher than the absorption coefficient (0.6 cm-1), is obtained. It is observed that the signal beam enhancement is in fact signal beam depletion for spatial frequencies higher than F
B, which is determined by fibre geometry. An unusually strong dependence of response time on the recording beams intensities ratio reflects the nonlinearities of the multi-two-wave mixing process. 相似文献
20.
Chen Sun Xiaomin Chen Junling Wang Guoliang Yuan Jiang Yin Zhiguo Liu 《Solid State Communications》2012,152(14):1194-1198
Multiferroic BiFeO3 and Bi0.92Dy0.08FeO3 ceramics were prepared to study their crystal structures and piezoelectric properties. BiFeO3 exhibits rhombohedral phase below 810 °C. Although Bi0.92Dy0.08FeO3 ceramic also shows rhombohedral phase at room temperature, it allows the coexistence of rhombohedral phase and orthorhombic phase at 460–650 °C. Both samples have maximum polarizations of >21 μC/cm2 and piezoelectric d33 values of ~37 pC/N at room temperature. Their polarized slices show the dielectric anomalies and impedance anomalies because of vibrating resonances below 500 °C, and the thickness vibration electromechanical coupling factor is ~0.6 and ~0.4 for BiFeO3 and Bi0.92Dy0.08FeO3, respectively. The vibrating resonances confirm piezoelectric responses. Furthermore, samples' impedance and resistance decrease fast with temperature increasing, which screens piezoelectric response above 550 °C. 相似文献