Giant electro-optic effect in nanodisordered KTN crystals

Abstract

The electro-optic (EO) effect in nanodisordered potassium tantalate niobate (KTN) crystal is quantitatively investigated. It is found out that the EO coefficient of nanodisordered KTN crystal depends not only on the cooling temperature but also on the cooling rate. A larger EO coefficient can be obtained by employing a faster cooling rate. A Kerr EO efficient (s(11) - s(12) = 6.94 × 10(-14) m(2)/V(2)) is obtained at a cooling rate of 0.45 °C/s. The enhanced EO efficient by employing a faster cooling rate will be greatly beneficial for a variety of applications such as laser Q switches, laser pulse shaping, high-speed optical shutters, and modulating retroreflectors.

Optical Properties of the Fresnoite Ba2TiSi2O8 Single Crystal

“…Based on its second-order optical nonlinearity, another feature of the BTS crystal is the electro-optic effect. Haussühl reported that BTS possesses a large electro-optical coefficient, which is of the same order of magnitude as that of KH 2 PO 4 , and so BTS is highly desirable for fabricating devices such as high-speed electro-optic modulators, optical shutters, and laser Q-switches which are used in the fields of laser modulation, optical communications and optoelectronics [10][11][12][13][14]. Furthermore, BTS has proved to be a novel stimulated Raman scattering active crystal, where the Raman gain is slightly greater than that of Ba(NO 3 ) 2 , and hence the crystal is suitable for solid-state Raman laser applications [15].…”

Macroscopic response and directional disorder dynamics in chemically substituted ferroelectrics

“…A key feature of disordered ferroelectrics is that they can manifest many of the properties of standard crystals, in terms of electrical, optical, and mechanical response, and still host a population of nanosized reconfigurable polar regions, the so-called polar nanoregions (PNRs). These are correlated mesoscopic regions of polarizations that are widely considered responsible for the giant electro-optic and piezoelectric effect [5,14,15]. Moreover, these PNRs can behave as liquid, solid, and even glassy systems, in the so-called nonergodic dipolar regimes, and all this in one and the same crystal structure, typically a large scale perovskite [16][17][18].…”

Temperature dependence of Kerr coefficient and quadratic polarized optical coefficient of a paraelectric Mn:Fe:KTN crystal

“…A larger EO coefficient can be obtained by employing a faster cooling rate, as the detailed analysis in Ref. 17. In addition, other factors may be from the inhomogeneity in the crystal (see Fig.2(d)) and the dielectric constants decreasing with increasing voltage at the same temperature T, as the detailed analysis in Ref.…”

“…Recently, research interests have converged on potassium tantalate niobate (KTN) crystal. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] KTN crystal, a perovskite-type oxide material, well recognized for its excellent EO performance where the index modulation is proportional to the square of the electric field, can realize rapid response, strong control of the refractive index and much lower driving energy comparing to LiNbO 3 for the same change ∆n in the refractive index. For this reason, KTN-based single crystal has been considered as promising materials, and has then been substantially investigated and successfully exploited in such diverse areas as EO deflection, [6][7][8] EO scanner, 9 a fast varifocal lens [10][11][12][13] and so on.…”

“…For this reason, KTN-based single crystal has been considered as promising materials, and has then been substantially investigated and successfully exploited in such diverse areas as EO deflection, [6][7][8] EO scanner, 9 a fast varifocal lens [10][11][12][13] and so on. 14,16,17 Mn:Fe:KTN crystal doped with both iron and manganese simultaneously are of particular interest because of its two competing subsystems of dipole moments and exhibits faster EO response than single-doped crystal. Generally, it is more significant to character the index redistribution when an electric field is applied to the photorefractive crystal and then to manipulate the OE process.…”