Growth,linear and nonlinear optical studies on guanidinium 4-nitrobenzoate (GuNB): An organic NLO material

Single crystals of guanidinium 4-nitrobenzoate (GuNB) were grown using solvent evaporation technique by mixing aqueous solutions of guanidine carbonate and 4-nitrobenzoic acid at ambient temperature. X-ray diffraction analysis characterized the unit cell parameters of the grown crystal and the crystal belongs to monoclinic system. The optical properties of the grown crystal have been studied by means of transmission measurements in the wavelength region between 200 and 1200 nm. The optical constants such as refractive index (n) and extinction coefficient (k) have been determined from the transmittance data. The optical band gap (E_g), the real and imaginary parts of the dielectric constant of the grown crystal was determined. Second harmonic generation (SHG) efficiency of the grown crystal has been studied using Nd:YAG laser and was measured as 3.2 times that of KDP. The low dielectric constant suggests the suitability of this compound material for NLO applications.     

Crystal growth,optical spectroscopy,and continuous-wave laser operation of Ho:KLu(WO4)2 crystals

We present the crystal growth, optical spectroscopy, and room temperature continuous-wave (CW) laser operation of monoclinic Ho:KLu(WO₄)₂ crystals. Macro defect-free crystals of several dopant concentrations were grown by top-seeded solution growth slow-cooling method. The evolution of unit cell parameters with holmium doping level and temperature was studied using X-ray powder diffraction. The spectroscopic properties were characterized in terms of room- and low-temperature optical absorption and photoluminescence. From low-temperature optical absorption measurements, the energy of the Stark levels was determined. Calculation of the emission and gain cross sections is presented. CW laser action was realized for 3 and 5 at. % Ho-doped KLu(WO₄)₂ by in-band pumping using a Tm:KLu(WO₄)₂ pump laser. A maximum output power of 507 mW with a slope efficiency of ~38 % with respect to the incident power was achieved at 2,080 nm with the Ho:KLu(WO₄)₂ laser.     

Synthesis,spectral, thermal and optical characterization of benzyltributylammonium trichlorobarium(II) monohydrate crystal

A new nonlinear optical semiorganic crystal, benzyltributylammonium trichlorobarium(II) monohydrate was grown by slow evaporation solution growth method at ambient temperature. The powder X-ray diffraction pattern of the crystal confirms its crystallinity. The absorption spectrum of the material shows a peak at 265 nm and no absorption observed in the entire visible region indicates that the compound can be used as a nonlinear optical material. The optical transmittance spectrum of the grown crystal shows a lower cut-off wavelength at 235 nm with transparency of 88%. Thermal stability of the crystal was studied by thermogravimetry-differential thermogravimetry and differential thermal analyses (TG-DTG and DTA). The differential scanning calorimetry (DSC) analysis shows thermal anomalies in the heating and cooling cycles that indicates the occurrence of a first order phase transition. The various characteristics absorption chemical bands and BaCl₃⁻ vibration were assigned through fourier transform infrared (FTIR) spectral analysis. The second harmonic generation efficiency (SHG) of the grown crystal was analyzed by Kurtz–Perry powder technique using Nd:YAG laser. The dielectric constant and dielectric loss of the compound decrease with increase in frequency.     

Growth,optical, mechanical,dielectric and theoretical properties of picolinium maleate NLO single crystal

Nonlinear optical single crystals of picolinium maleate (PM) were grown by slow evaporation method. The grown crystal was subjected to single crystal X-ray diffraction analysis to confirm that the crystal belongs to the monoclinic crystal structure with space group P2₁/c. The optical transmission range of the grown crystal was measured by UV–Vis–NIR region with the lower cut-off wavelength as 330 nm. The optical bandgap is found to be 3.75 eV. Mechanical strength of the grown crystal was analyzed using Vickers microhardness tester. Dielectric constant and dielectric loss of picolinium maleate are measured in the frequency range from 50 Hz to 5 MHz at different temperatures. Further, electronic properties, such as valence electron plasma energy, Penn gap, Fermi energy and electronic polarizability of the grown crystal have been estimated.     

The growth,thermal and nonlinear optical properties of single-crystal GdAl3(BO3)4

The nonlinear optical single-crystals GdAl₃(BO₃)₄ (GAB), space group R32, were grown by the top-seed solution growth (TSSG) method. The thermal properties and the nonlinear optical characteristics have been investigated. The two principal coefficients of thermal expansion along (100) and (001) were measured to be 5.30 × 10⁻⁶, 1.88 × 10⁻⁵ K⁻¹. The transmission spectrum was measured and the second-harmonic generation (SHG) was presented. By way of our designed cross superimposed laser crystal multiplier, the frequency doubling laser at wavelength 457.5 nm was measured to be 18.2 mW and the facular properties indicated the multiplier contributed to the improvement of the frequency doubling conversion efficiency.     

Thermal, mechanical, electrical, linear and nonlinear optical properties of a nonlinear optical l-ornithine monohydrochloride single crystal

Optically transparent semiorganic nonlinear optical bulk single crystal of l-ornithine monohydrochloride (LOMHCL) of dimension 11×3×2 mm³ has been grown from its aqueous solution by slow solvent evaporation technique. The grown crystal was characterized by powder X-ray diffraction to confirm the crystal structure. Investigation has been carried out to assign the vibrational frequencies of the grown crystals by Fourier transform infrared spectroscopy technique. Thermal behavior of the grown crystals was studied by thermogravimetric analysis. The second harmonic generation (SHG) efficiency of LOMHCL was determined by Kurtz and Perry powder technique. The optical absorption study confirms the suitability of the crystal for device applications. The mechanical properties of the grown crystals have been studied using Vickers microhardness tester. Dielectric and photoconductivity studies are also carried out for the grown samples.     

Synthesis, growth, spectral, thermal and photoluminescence properties of a new semiorganic NLO crystal—Thiosemicarbazide lithium chloride [TSLC]

Thiosemicarbazide lithium chloride [TSLC] a new semiorganic nonlinear optical crystal has been synthesized. Single crystals by TSLC have been grown by slow evaporation solution growth technique at room temperature. Chemical composition of the synthesized material was confirmed by elemental analysis. Powder X-ray diffraction (XRD) pattern of the grown crystal has been studied. Functional groups present in the materials were identified by FT IR spectral analysis ranging between 4000 and 450 cm⁻¹. The optical transmission was studied through UV-vis spectrophotometer. Thermal analysis is carried out on the crystal and inferred to be stable at 176 °C. The second harmonic generation (SHG) of the TSLC crystal was confirmed using Nd:YAG laser and also fluorescence spectral analysis is carried out for the TSLC crystal.     

A new NLO Material: L-Asparagine thiocyanate (LATC) for opto-electronic applications

L-asparagine monohydrade thiocyanate (LATC), which is potentially a non-linear optical crystal, was grown by the conventional slow evaporation solution technique (SEST) using doubly de-ionized water at room temperature. The lattice parameters were found by using single crystal X-ray diffraction analysis. Perfection of the grown crystal was confirmed by powder X-ray diffraction. The various functional groups were identified from FT-IR analysis. The optical parameters, such as the optical absorption, the band gap, photoluminescence and second harmonic generation (SHG), were analyzed on the grown crystal. The induced surface laser damage threshold was measured using a Q-switched Nd:YAG laser. The thermal behavior and stability of the grown crystal was analyzed by TG/DTA analysis. The dielectric constant (ε_r) and dielectric loss (tanδ) as a function of frequency has been investigated at different temperatures. The mechanical property of the grown crystal was studied using the Vickers micro hardness method.     

Studies on physico-chemical properties of hydroxyethylammonium (l) tartrate monohydrate single crystals

In this paper, we report the growth and characterization of hydroxyethylammonium (l) tartrate monohydrate single crystals grown by slow evaporation solution technique. The X-ray diffraction analysis reveals that the crystal belongs to the monoclinic system having P2₁ space group. Photoinduced optical absorption effects were studied on the crystalline samples irradiated with CW 532 nm (green) and 689 nm (red) laser wavelengths. The relative second harmonic generation efficiency of the title crystal was found to be 1.4 times larger than that of KDP crystal. The thermal, mechanical, dielectric and optical studies of the single crystals were carried out to propose the material for useful applications. The reflectance and refractive indices were also evaluated from optical transmission spectrum. Further the electronic excitation calculations were carried out to understand the charge transfer mechanisms.     

Third order nonlinear optical properties of potassium dichromate single crystals by Z-scan technique

Single crystal of potassium dichromate (KDC) has been grown from aqueous solution by slow evaporation technique. The lattice parameters of the grown crystal were determined by X-ray diffraction analysis. The optical absorption studies reveal that the crystal has UV cut-off wavelength around 240 nm. Thermo gravimetric and differential thermal (TGA/DTA) studies revealed that the crystal thermally stable up to 397.1 °C. The mechanical strength of the grown crystal was carried out by Vickers micro hardness test. The crystal perfection was confirmed by etching studies. Third order nonlinear optical studies was performed using by single beam Z-scan technique using continuous Nd:YAG laser. Closed aperture Z-scan studies reveal the negative nonlinearity in the crystals and open aperture Z-scan reveals the saturation absorption. Also various parameters such as nonlinear refractive index n₂, absorption co-efficient β and nonlinear optical susceptibility χ⁽³⁾ were calculated for the grown crystal.     

Studies on the optical and mechanical properties of organic nonlinear optical 1-(4-fluorostyryl)-4-nitrostilbene (FNS) single crystal

A new organic nonlinear optical material 1-(4-fluorostyryl)-4-nitrostilbene (FNS) has been synthesized and single crystals of FNS were grown using solvent evaporation solution growth technique (SESGT) by 2-butanon solvent. Single crystal x-ray diffraction analysis reveals the unit cell parameters of the grown crystal are a = 9.494(4) Å, b = 9.864(2) Å, c = 19.501(7) Å and it belongs to monoclinic system with noncentrosymmetric space group. Optical transmittance of the grown crystal has been studied by UV-Vis-NIR spectrum. The optical properties of FNS have been studied by means of optical transmittance measurements in the wavelength range of 190–1100 nm The optical constants were calculated from the optical transmittance (T) data such as refractive index (n), extinction coefficient (k) and reflectance (R). The optical band gap (E_g) of FNS is 3.27 eV with direct transition. The complex dielectric (?) constant of the grown FNS crystal was determined. The second harmonic generation (SHG) efficiency of the grown FNS crystal has been studied by using Kurtz-Perry powder technique and it shows 12 times relatively greater than KDP.     

Optical, thermal, dielectric and ferroelectric behaviour of sodium acid phthalate (SAP) single crystals

Sodium acid phthalate (SAP), an efficient semi-organic crystal having dimensions 17×8×2 mm³ has been grown from aqueous solution by slow evaporation technique at room temperature within the period of 2 weeks. The lattice parameters of the grown crystals were determined using single-crystal X-ray diffraction analysis. The presence of functional groups was estimated qualitatively by Fourier transform infrared (FTIR) analysis. The band gap energy was determined using optical absorption studies. The TG/DTA analysis reveals that the SAP crystal is thermally stable up to 141.6 °C. The dielectric constant and dielectric loss was studied as a function of frequency and the corresponding activation energy (E_a) has been calculated for the grown crystal. Scanning electron microscope studies enunciate the ferroelectric domain patterns of the SAP crystal. Ferroelectric property of the grown crystal was confirmed by hysteresis loop studies.     

A new metal-organic nonlinear optical material: L-Asparagine Indium chloride (LAIn) for photonics application

Single crystal of l-Asparagine Indium chloride (LAIn), a new semi-organic crystal was grown by slow evaporation method with deionized water as solvent at ambient condition. The crystal structure of LAIn has been determined by single crystal X-ray diffraction and the result shows that the crystal belongs to the orthorhombic system with P2₁2₁2₁ space group. The crystalline nature of grown crystal was analyzed by powder X-ray diffraction analysis. Optical parameters, such as absorbance, transmittance and optical band gap energy were analyzed using UV–Vis NIR transmittance data at the range of 190–800?nm. The ultraviolet (UV) emission nature of the sample was established from the sharp emission peaks in photoluminescence (PL) spectrum. The photo conductivity test exhibits that the grown crystal has positive photo conductive nature. The induced surface laser damage threshold (LDT) for the grown crystal was measured using Nd:YAG laser. The nonlinear optical efficiency of the LAIn crystal was studied using modified Kurtz-Perry powder technique. The hardness, Meyer index, yield strength and elastic stiffness constant were calculated for the grown crystal using Vickers microhardness tester. The variation of dielectric constant and dielectric loss of the grown crystals as a function of frequency has been investigated at different temperatures. The melting point and thermal stability of the LAIn single crystal have been studied by thermo gravimetric analysis and differential thermal analysis (TG/DTA).     

Crystal growth and characterization of l-phenylalaninium trichloroacetate—A new organic nonlinear optical material

Amino acid based crystals exhibit excellent nonlinear and electro-optical properties. A new nonlinear optical single crystal l-phenylalaninium trichloroacetate (LPTCA) belonging to the amino acid group was grown by the slow evaporation solution growth method. The grown crystals have been subjected to powder X-ray diffraction studies to identify the crystalline nature. Single crystal X-ray diffraction study showed that LPTCA belongs to monoclinic crystal system. Fourier transform infrared study is used to confirm the presence of various functional groups in the grown crystal. Optical transparency of the grown crystals was investigated by UV-vis-NIR spectrum. The lower optical cutoff wavelength for this crystal is observed at 254 nm and energy band gap is 4.89 eV. Thermal properties of the LPTCA crystal were studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques, which indicate that the material does not decompose before melting. The melting point of grown crystal was observed to be 136 °C in a melting point apparatus. The existence of nonlinear optical (NLO) property of LPTCA was confirmed by second harmonic generation test using Nd:YAG laser fundamental wavelength of 1064 nm.     

Effect of Co2+ on the growth,optical properties and laser damage threshold of potential nonlinear optical l-alanine single crystal

Good transparent bulk single crystals of pure l-alanine (LA) and cobalt doped LA crystals have been synthesized and successfully grown by slow-cooling method from their aqueous solutions. The concentration of metal dopants in the mother solution with 0.5 mol% for cobalt was carried out individually and crystals were obtained with well defined morphology. The as grown metal doped and pure single crystals were characterized by single crystal XRD studies which confirm that the incorporation of metallic dopants has not changed the basic structure of the parent crystal. The absorption of these crystals was analyzed and the result confirms that they possess low absorption in the range 230–1100 nm. Fourier transform infrared (FTIR) spectroscopy was carried out to investigate the molecular vibrations of these crystals and to confirm the incorporation of the dopants. The thermal properties have been studied by TGA/DTA curves. The EDAX measurement and surface morphology were studied for pure and metal doped LA crystals. The second harmonic generation (SHG) signals were observed using Nd: YAG laser with fundamental wavelength of 1064 nm in pure and metal doped crystals. The laser damage threshold was measured for pure and metal doped LA crystals and also tested by using a Q-switched Nd: YAG laser showed enhanced LDT value for metal (Co²⁺) doped LA crystal compared to pure LA crystal due to the metallic substitutions thus proving their useful candidature for nonlinear optical applications.     

Growth,structural, spectral,thermal, electrical and optical characterization of a novel optical material: Triethanolamine picrate single crystals for optical applications

The Triethanolamine picrate (TEAP) single crystal was grown by slow evaporation technique. The grown crystal crystallizes in monoclinic system and P2_1/C is the space group determined by Single crystal X-Ray diffraction method. The vibrational modes and functional groups were elucidated from Fourier Transform InfraRed (FTIR) spectra and Fourier Transform Raman (FT-Raman) spectra. The Ultraviolet - Visible (Uv-Vis) studies accomplished the excitation wavelength of the grown crystal is around 203 nm and 354 nm and it is suitable to exhibit second harmonic generation signal. From the absorption data, remarkable optical properties such as optical band gap energy, extinction coefficient were evaluated. The mechanical strength of the grown crystal was examined by Vickers micro hardness test. The temperature of decomposition was confirmed by Thermo Gravimetric / Differential Thermal Analysis (TG/DTA). Kurtz and Perry technique were confirmed the Non-Linear Optics (NLO) property of the crystal. The electrical properties were explained using Dielectric studies.     

Growth,spectral, optical,and dielectric studies on novel semiorganic NLO single crystal: d-phenylglycine hydrochloride

Good quality novel semiorganic nonlinear optical single crystal of d-phenylglycine hydrochloride has been grown from the aqueous solution by low temperature solution growth method. X-ray diffraction reveals that the crystal crystallises into orthorhombic system with noncentrosymmetric space group P2₁2₁2₁. Experimental parameters are evaluated based on single-crystal XRD and the calculated values of the polarisability were compared with the values of polarisability using Clausius–Mossotti equation. The functional groups present in the grown crystal were confirmed by Fourier transform infrared spectral analysis. The ¹H and ¹³C FT–NMR has been recorded to elucidate the molecular structure. Ultraviolet–visible-near infra-red absorption studies on this crystal reveal that the minimum absorption region is around 228 nm. The optical band gap of the crystal was found to be 2.9 eV. The scanning electron microscope study has been carried out to determine the surface morphology of the grown crystal. Photoluminescence studies show that the material emits violet fluorescence. Thermal studies bring forth that the crystal is thermally stable up to 255 °C. Dielectric studies reveal that both the dielectric constant and dielectric loss decrease with the increase in frequency as like the typical semiorganic nonlinear optical crystals such as bisthiourea zinc chloride, bisthiourea cadmium chloride and l-arginine dihydrogen phosphate. Electrical conductivity measurements were carried out and the Arrhenius plot is used to determine the value of activation energy. The Kurtz powder analysis on the crystal confirms the existence of second harmonic generation properties. The SHG efficiency was found to be 1.15 times that of KDP crystal.     

Crystal structure,vibrational, and optical investigations of semiorganic nonlinear optical crystal: Bi3[CS(NH2)2]9Cl9· 2H2O

Tribismuthnonakisthioureanonachloride dihydrate (TBNTNC), a semiorganic nonlinear optical (NLO) material useful for frequency doubling in the IR region, has been grown by single diffusion gel technique. The grown crystal was confirmed by single crystal XRD and it crystallizes in triclinic system having P₁ space group. Vibrational analysis was carried out for the grown crystal. FTIR and FT‐Raman spectral studies were performed for analyzing and assigning the phonon vibrations and to identify the functional group contribution. The optical transmission study was carried out to examine the transmission ability of the crystal. The nonlinear optical property was confirmed by relative second harmonic generation measurement using Nd:YAG laser. Copyright © 2009 John Wiley & Sons, Ltd.     

Growth and characterization of an efficient nonlinear optical single crystal: Urea p-nitrophenol

An organic nonlinear optical single crystal of urea p-nitrophenol has been synthesized and grown by slow evaporation solution growth technique. The grown crystals were characterized by single crystal and powder X-ray diffraction analysis and it was found to be the structure of the crystal belongs to triclinic system. The various functional groups were identified by FT-IR and Raman spectral analysis. Thermal stability of the grown crystal was studied by TGA/DTA. The optical properties of the grown crystals were analyzed by UV–vis. The mechanical properties of the grown crystal were studied by Vickers microhardness measurements. Nonlinear optical property of the crystal was confirmed using the Kurtz and Perry powder technique and a study of its SHG efficiency in comparison with KDP has made.     

Synthesis,crystal growth,and characterization of piperazinediium bis (4-aminobenzoate) dihydrate - An efficient third-order nonlinear optical single crystal for opto-electronic applications

Organic compound of protonated Piperazinediium bis (4-aminobenzoate) dihydrate C₄H₁₂N₂²⁺2(C₇H₆NO₂⁻).2(H₂O) (PZ4AB) was synthesized and crystal was grown by slow evaporation solution growth technique. Powder X-ray diffraction and High resolution X-ray diffraction studies affirmed the crystalline perfection of the grown crystal. Fourier transform infrared spectral analysis ascertained the frequencies of various functional groups present in PZ4AB crystal. Optical transmittance and optical band gap estimation explored the optical phenomena of PZ4AB crystal. The laser-induced surface damage threshold value of PZ4AB crystal was measured to be 1.0615 GW/cm² for the 1064 nm Nd:YAG laser radiation. From Thermogravimetric and differential scanning calorimetric studies, the stability of PZ4AB crystal was ascertained. The dielectric manner was endowed as a function of frequency and temperature. The mechanically soft nature of the crystal was assessed by Vickers hardness measurement which exhibited the reverse indentation size effect. The nonlinear refractive index, absorption coefficient and the third-order nonlinear susceptibility of crystal were divulged by Z-scan technique.