Jiang Min-hua

A new organometallic nonlinear optical material — triallylthiourea mercury bromide (ATMB) crystal: growth and structure

Abstract A new organometallic nonlinear optical crystal triallylthiourea mercury bromide (ATMB) with space group R3c has been synthesized and grown by the temperature lowering method from aqueous solution. Its powder second harmonic generation (SHG) intensity is 2.5 times higher than that of urea. The crystal structure of ATMB is reported and also the relations between the crystal structure and nonlinear optical (NLO) effects are discussed.

A new nonlinear optical material-organometallic complex tri-allylthiourea cadmium chloride

Tri-allylthiourea cadmium chloride (ATCC), an organometallic complex, is a new nonlinear optical material with high second harmonic generation (SHG) effect. Transparant single crystal of 30 × 30 × 25 mm has been grown. Comprehensive studies of crystal growth, structure and general properties have been carried out. The results show that organometallic complexes are promising nonlinear optical materials for wide applications.

Excited emission and self-frequency-doubling effect of NdxY1-xAl3 (BO3)4 crystal

Using dye laser as pumping light source, we have first realized on NYAB crystal the laser self-frequency doubling run from 1.06μm to 0.53μm. The threshold energy is less than 4mJ; conversion efficiency is 6.2%, and the self-frequency-doubling green light output energy is 2.5mJ.

Non-linear optical properties of DMIT derivatives

A number of new DMIT derivatives have been synthesized and their structures have been determined. Among them only chiral BNPT-DTO has significant powder SHG efficiency which varies strongly with the crystal growth solvent and the crystalline temperature; this corresponds to its variability in molecular configuration. DMIT derivatives are also characterized by good crystal habits, good physicochemical stabilities and potentially strong S ⋯ S molecular interactions.

Growth, Defects and Non-critical Phase Matching of Nb Doped KTP Crystals

A series of Nb doped KTP crystals are grown with seed flux method and flux pulling method. The results of our investigation on growth, morphology defects of the crystals are reported in this paper. We obtained the relationship between Nb contents and second-harmonic generation angles of the crystals. Noncritical phase matching has been realized by 4% Nb doped KTP crystal for Nd:YAG laser 1.06 μm output.

Two-Photon Absorption and Optical Power Limiting Based on New Organic Dyes

Two new organic dye samples J and L with a large two-photon absorption (TPA) cross section have been reported. The linear absorption spectra show that there is no linear absorption at the wavelength from 650 to 1200 nm. The molecular TPA cross section was measured to be as high as 2.59×10-47 cm4s and 2.98×10-47 cm4s at 1064 nm for samples J and L, respectively. The input-output curves indicate that there is a clear optical power limiting behaviour when the input intensity is higher than 0.4 GW/cm2. Furthermore, the basic theory of the TPA process has been discussed.

Study of properties and structural features of some new organic and organometallic nonlinear optical crystals

Certain organic crystals have attracted much attention owing to their nonlinear optical coefficients, at least one to two orders of magnitude above those of inorganic nonlinear optical materials. However, none of them has so far actually been applied in frequency conversion devices used with high-, medium- or low-power lasers. In this article the authors discuss the major factors affecting frequency conversion efficiency and examine characteristics of some frequently mentioned organic crystals. The properties and structure characterization of a new type of nonlinear optical crystal are also reported and discussed.

Two-photon absorption-induced emission properties of dye HMASPS doped polymer

The 0.01M two-photon absorption dye trans-4-[p-(N-hydroxyethyl-N-methylamino)styryl]-N-methyl-pyridinium p-toluene sulfonate (HMASPS) doped polymer has been prepared. When pumped by the picosecond pulse from the pulsed mode-locked Nd:YAG laser, the polymer emits more intense upconverted fluorescence and superradiance compared to the solution sample of the dye. The two-photon pumped lasing with oscillating pulses has also been obtained. Compared to the dye in its solution state, the emission spectra of the polymer are all blueshifted. The polymer has a long upconverted fluorescent lifetime of about 4.041?0.04?ns.

Crystal growth of high Tc superconductors YBa2Cu3Ox, Bi3Sr3CaCu2.5Ox and Pb0.6Bi3Sr2CaCu3Ox

Single crystals of YBa 2 Cu 3 O x , Bi 3 Sr 3 CaCu 2.5 O x and Pb 0.6 Bi 3 Sr 2 CaCu 3 O x have been grown by the flux method. The crystals obtained have sizes varying from 2.5 x 2.0 x 0.1 mm 3 to 10 x 4 x 3 mm 3 . These crystals have an orthorhombic structure with cell parameters a = 3.838(1) A, b = 3.871(1) A and c =11.738(4) A (YBa 2 Cu 3 Ox); a = 5.39 X, b = 5.37 A and c = 31.01 A (Bi 3 Sr 3 CaCu 2.5 Ox); and a = 5.38 A, b = 5.34 A, c = 30.55 A (Pb 0.6 Bi 3 Sr 2 CaCu 3 Ox). Measurements of resistivity and AC susceptibility confirmed that these crystals are bulk superconductors with T c (zero) of 91.4, 90 and 82 K, respectively. Differential thermal analysis (DTA) measurements were made to study the crystal growth process and thermal properties of these crystals.

Fluorescence of a New Phenanthrolin Derivative Sensitive to DNA Induced by Single- and Two-photon Excitation

A novel two-photon absorption (TPA) material with phenanthrolin as acceptor (BSIPB) has been firstly synthesized and studied as possible fluorescence probe for nucleic acids detection. The single-photon and two-photon fluorescence properties of the dye in the unbound state and in DNA complexes were investigated. Some quantum yields and TPA cross sections at important points were calculated. The results showed that BSIPB can be used as an efficient fluorescent probes for DNA detection and imaging under both single-photon excitation (SPE) and two-photon excitation (TPE).