• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.396-400
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• 1998

The physical properties of KLN single crystals very significantly according to the $Nb_2O_5$ content in grown crystal, therefore, it is very important to control the composition of KLN single crystals. In this study, KLN single crystals of high content $Nb_2O_5$ were grown by temperature fluctuation and TSSG (Top-seeded solution growth) methods with increasing the $Nb_2O_5$ content of starting solution. To investigate the existence of defect due to the increase of $Nb_2O_5$ content, dielectric and optical properties were measured. Due to the increase of defects in grown KLN single crystal, the shift of cutoff-frequency to lower energy and a broad Curie range, which shows the DPT (diffuse phase transition) characteristics, were observed.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.167-185
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• 1999

In the present paper, KLN crystals have been grown along <001>, <100> and <110> directions by the top seeded solution growth (TSSG) method from Li-richer melts with different compositions. The morphologies of KLN crystals grown along different directions have been studied, and the well-developed facets have been unambiguously indexed using X-ray goniometer and stereographic projection analysis. The growth mechanism and defects such as cracks and inclusions were discussed on the basis of observations of facets on the crystal-melt interfaces. The crystal compositions were determined by chemical analysis method. The structure and lattice constants of KLN crystals were determined and calculated on the basis of XRD data by using TREOR90 and PIRUM programs. The Curie temperature and optical absorption were determined by dielectric constant peak and spectrum measurements, respectively. The blue SHG characteristics of a KLN sample were also investigated using a pulsed dye laser. PACS: 42.70.M;81.10;81.10A;42.65.K.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.396-401
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• 1999

In the present paper, potassium lithium niobate(KLN) crystals have been grown along <001>, <100> and <110> directions by the top seeded solution growth (TSSG) method from Li-richer melts with different compositions. The morphologies of KLN crystals grown along different directions have been studied, and the well-developed facets have been unambiguously indexed using X-ray goniometer and stereographic projection analysis. The growth mechanism and defects such as cracks and inclusions were discussed on the basis of observations of facets on the crystal-solution interfaces. The crystal compositions were determined by a chemical analysis method. The structure and lattice constants of KLN crystals were determined and calculated on the basis of XRD data by using TREOR90 and PIRUM programs. The Curie temperature and optical absorption were determined by dielectric constant peak and spectrum measurements. respectively. The blue second harmonic generation (SHG) characteristics of KLN sample were also investigated using a pulsed dye laser.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.2
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• pp.94-99
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• 1995

Potassium lithium niobate (KLN) crystals, grown by the micro pulling down $({\mu}-PD)$ method, have been considered on the interchange between incongruent melt composition and second harmonic generation (SHG) properties because of the sensitive interaction. Correlation between the composition of crystals and the wavelength of SHG applications from ultra - violet to green region was found. Also, the ${\mu}-PD KLN$ KLN crystals showed a homogeneity of noncritical phase matching and an excellent SHG property which is converted to blue laser light with half wavelength by the red irradiation.

• Journal of Magnetics
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• v.16 no.2
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• pp.108-113
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• 2011

The electron spin resonance lineshape (ESRLS) function for the electron spin resonance linewidth (ESRLW) of $Cr^{3+}$ (S = 3/2) in ferroelectric lithium niobate single crystals doped with 0.05 wt% of Cr, is obtained by using the projection operator technique (POT), developed by Argyres and Sigel. The ESRLS function is calculated to be axially symmetric about the c - axis and analyzed by using the spin Hamiltonian $H_{SP}={\mu}_B(B{\cdot}{^\leftrightarrow_{g}}{\cdot}S)+S{\cdot}{^\leftrightarrow_{D}}{\cdot}S$ with the parameters g = 1.972 and D = $0.395\;cm^{-1}$. In the ca plane, the linewidths show a strong angular dependence, whereas in the ab plane, they are independent of the angle. This result implies that the resonance center has an axial symmetry along the c - axis. Further, from the temperature dependence of the linewidths that is shown, it can be seen that the linewidths increase as the temperature increases, at a frequency of v = 9.27GHz. This result implies that the scattering effect increases with increasing temperature. Thus, the POT is considered to be more convenient to explain the scattering mechanism as in the case of other optical resonant systems.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.1
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• pp.19-24
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• 1995

Large size potassium lithium niobate (KLN) crystals with dimensions of $8{\times}6{\times}2 mm^3$ were grown by the top - seeded solution growth (TSSG) method. The extraordinary refractive index $n_e$at the second harmonic frequency for KLN crystal depends on the composition and decreases in this crystal due to the large Li content. KLN crystal was characterized by observation in UV - VIS spectrometry. It is transparent from the ultraviolet to infrared spectral regions that the transmission limit and cut- off wavelength are about 350 and 380 nm.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.168-168
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• 2009

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.111-114
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• 1998

Lithium Niobate {{{{ { LiNbO}_{ 3} }}}} single crystals grown by Czichralski method at the congruent composition, have ferroelectric microdomains. These microdomins were investigated by chemical etching with hydrofluoric acid (HF) AND NITRIC ACID ({{{{ { HNO}_{3 } }}}}), and by us ing optical microscopy, scanning electron microscopy and atomic force microscopy

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.222-223
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• 2001

Optical parametric oscillator(OPO) has been used to generate coherent and tunable laser source with birefringent phase-matching technique in various nonlinear materials. In birefringent phase-matching, the output wavelength is controlled with angle or temperature tuning of the refractive index. However these tuning methods have several limitations such as restriction of tuning wavelength due to reasonable angular and temperature tuning ranges, Poynting vector walk-off which limits the interaction length, and thermal stabilization time. (omitted)

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.215-216
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• 2008