Transparent single crystals of potassium dihydrogen phosphate (KDP) were grown by modified Sankaranarayanan–Ramasamy (SR) method. The band gap energy for the KDP crystals was calculated from optical transmission spectrum. The theoretical calculations to determine the optical constants of the material and a technique for photonic band gap tuning, which is essentially required to develop the optoelectronic devices, were determined using the optical studies. Further, the Vicker's micro hardness as well as parameters such as fracture toughness (Kc), brittleness index (B) and yield strength (σv) are presented.

Growth, theoretical and optical studies on potassium dihydrogen phosphate (KDP) single crystals by modified Sankaranarayanan–Ramasamy (mSR) method

Bulk crystal growth and characterization of non-linear optical bisthiourea zinc chloride single crystal by unidirectional growth method

Conventional slow evaporation and Sankaranarayanan–Ramasamy (SR) method grown diglycine zinc chloride (DGZC) single crystal and its comparative study

Controlling the optical constants of PVC nanocomposite films for optoelectronic applications

We present the design of fluoro derivatives of B10H14 and Li@B10H14 baskets. A synergistic effect of conical push and inward pull (reported independently in previous lithium nonlinear optical (NLO)...

Capturing a synergistic effect of a conical push and an inward pull in fluoro derivatives of Li@B10H14 basket: toward a higher vertical ionization potential and nonlinear optical response.

Studies on optical, mechanical and transport properties of NLO active L-alanine formate single crystal grown by modified Sankaranarayanan Ramasamy (SR) method

Optical absorption in photonic crystals of potassium acid phthalate has been measured at room temperature, from which the band gap has been determined and the optical band gap was calculated by using absorption spectrum. The analysis of absorption coefficient in the absorption region reveals a direct band gap of 3.70 eV. Further this study includes the theoretical calculations to determine the optical constant of the material and a technique for photonic band gap tuning which is minimally required to develop the optoelectronic device. It was confirmed that potassium acid phthalate crystal has maximum transparency in the entire visible region and hence it exhibits industrial application oriented properties. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Investigation of optical band gap in potassium acid phthalate single crystal

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

Single crystals of nonlinear optical l -histidine hydrochloride monohydrate (LHC) were grown in an aqueous solution by the unidirectional crystal growth method within a period of 45 days along (1 0 1) plane. The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm their orthorhombic structure having space group P2 1 2 1 2 1 . Values of several physical parameters were determined for the grown crystal. Optical transmission studies revealed very low absorption and band gap energy was calculated for the LHC crystals. Further, some optical constant were also determined for the grown crystals. Anisotropy in Vicker's microhardness led to the assessment of fracture toughness, brittleness index and yield strength for the synthesized crystals. Nonlinear optical studies were carried out for the grown crystal and second harmonic generation (SHG) efficiency was found to be three times that of KDP crystals.

Spectral, optical and mechanical studies on L-histidine hydrochloride monohydrate (LHC) single crystals grown by unidirectional growth technique

Good optical quality single crystals of zinc hydrogen phosphate (ZnHPO4) having dimensions up to 8×2×2 mm3 have been grown with the aid of sodium meta silicate gel. Single crystal XRD studies confirm that the crystal belongs to the orthorhombic system with space group P212121. The functional groups present in the crystals were confirmed using FTIR technique. Optical absorbance shows very low absorption in the entire visible region. Differential thermal and thermo gravimetric analysis confirmed that the crystal is stable up to 193°C. Photoconductivity study reveals positive photoconductivity in the presence of photo active centers formed by trap energy levels. The NLO activity of the crystal was confirmed by Kurtz powder technique. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

S. Dinakaran

Papers

Studies on optical, mechanical and transport properties of NLO active L-alanine formate single crystal grown by modified Sankaranarayanan Ramasamy (SR) method

Investigation of optical band gap in potassium acid phthalate single crystal

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

Spectral, optical and mechanical studies on L-histidine hydrochloride monohydrate (LHC) single crystals grown by unidirectional growth technique

Growth and characterization of nonlinear optical zinc hydrogen phosphate single crystal grown in silica gel