Photon excitation enabled large aperture space-charge-controlled potassium tantalate niobate (KTN) beam deflector

Abstract

To overcome the depth limitation of the space-charge-controlled (SCC) potassium tantalate niobate (KTN) deflectors, we report in this paper a method of increasing the aperture of SCC-KTN deflectors by harnessing the physical mechanism of blue light photon excitation. The experimental results show that the deflection angle can be increased from 0.7 mrad without the blue light excitation to 2.5 mrad with the blue light excitation at a penetration depth of 5 mm under the same external applied voltage, which is consistent with the theoretical analysis. This represents a substantial increase in the deflection angle at a much deeper penetration depth, which can be very useful for applications such as high speed 3D printings and displays.

Improving the Electro-Optical Deflection Performance of KTN Crystals Based on the Temperature Compensation Effect

“…In recent years, KTN crystals have been used to make dynamic optical waveguides, electro-optical modulators, high-speed scanners, and other optoelectronic functional devices. − However, there are still some problems to be solved in the practical application of KTN crystals, and researchers have conducted in-depth studies on them. For example, Yin et al solved the problem that the charge injection depth is limited by the bound charge and used the physical mechanism of excitation of bound electrons by blue-light photons to increase the charge injection depth and increase the deflection angle. Chen et al, using an applied electric field, can significantly increase the dielectric constant and increase the deflection angle by a factor of 3.…”

“…Non-mechanical beam deflectors can be further categorized into liquid crystal-phased array deflectors, acousto-optical deflectors, electro-optical deflectors, and others. The electro-optical crystal beam deflector uses the electro-optical effect of the crystal to create an isotropic transparent medium that exhibits optical anisotropy under the action of an electric field. − The refractive index of the substance changes with the applied electric field. Electro-optical deflectors can be divided into two types: one that varies linearly with the electric field, called the Pockels effect, such as LiNbO 3 or KDP, and the other that demonstrates the Kerr effect, causing the electric field to change the refractive index in a quadratic fashion.…”

Reversible Rectification of Microscale Ferroelectric Junctions Employing Liquid Metal Electrodes

“…Recently, ferroelectric junctions have attracted intensive attention for potential applications in next-generation memory devices, − switchable diodes, and electro–optical modulators . Potassium tantalate niobate (KTa 1– x Nb x O 3 , KTN) crystal as a ferroelectric material has also attracted considerable attention due to its potential applications in functional optoelectronic devices on the basis of its unique characteristics, − such as giant piezoelectric coefficients, , large electro-optical effects, , adjustable polar nanoregions, and the electrocaloric effect . However, the electrical properties of KTN particles upon light illumination have been rarely studied.…”

In-Situ Growth of Au on KTaO3 Sub-Micron Cubes via Wet Chemical Approach for Enhanced Photodegradation of p-Nitrophenol

“…Potassium tantalates and their derivatives are wide-band gap semiconductors that are extensively applied in many fields, including gas phase condensation, photo-transporting, photo-detector, air-treatment, photo-conducting and photo-electronic response [1,2,3,4,5,6]. Furthermore, potassium tantalates are considered one kind of the most stable photoelectric catalysts and are widely employed in photonically-driven CO 2 reduction [7,8], water splitting and hydrogen evolution [7,8,9,10]. While potassium tantalates exhibit excellent stability in photocatalysis, their absorption locates at Ultra-violet (UV) range and limits the employment of visible light.…”