Linear and nonlinear optical properties of trigonal borate crystals K7MIn2-xYbx(B5O10)3 (M = Ca, Sr, Ba; x=0…2) with isolated B5O10 units

Noncentrosymmetric borates K7MIn2−xYbx(B5O10)3 (M = Ca, Sr, Ba; x = 0…2) were synthesized by the solid state reaction and the crystals were successfully grown by the top seeded solution growth method using the K2O-B2O3-MF2 flux. According to Rietveld refinement, the crystal structure belongs to the noncentrosymmetric R32 space group. Also, the octahedrally coordinated In atoms are located at wide ranges ∼8 Å which may be promising for phosphor and laser applications. Samples with ytterbium show a characteristic emission band in the range of 950–1050 nm related to the 2F5/2 → 2F7/2 transition of Yb3+ ions that is commonly used for laser generation. IR, Raman and absorption spectra were obtained for the samples as well. The short cut edge of UV absorption, SHG intensity comparable with KDP and low concentration quenching of luminescence suggest that the K7MIn2−xYbx(B5O10)3 borates are promising self-frequency doubling materials

Study of RBO3-ScBO3 phase diagrams and RSc3(BO3)4 orthoborates (R = La, Pr and Nd)

RBO3 – ScBO3 diagrams (R = La, Pr and Nd) were investigated by the solid state synthesis and DSC methods. In these systems the solid solutions based on RSc3(BO3)4, RBO3 and ScBO3 were identified. The single crystals of RSc3(BO3)4 were grown by spontaneous crystallization method from LiBO2-LiF flux. The borates containing Pr and Nd have typical luminescence in the red/IR range which correlated to Pr3+: 3P0 → 3H6, 1D2 → 3H4 (~ 620 nm), and 3P0 → 2F2, 1D2 → 3H5 (~ 655 nm) and Nd3+ electron transitions 4F3/2 → 4I9/2 (875 nm) and 4F3/2 → 4I11/2 (1055 nm). The luminescence intensity strongly depends on the concentration of the fluorophores. In addition the SHG efficiency (for radiation of Nd:YAG laser, 1064 nm) for grown PrSc3(BO3)4 crystals was found to be 1.85 times higher (deff) than for KDP revealing its high potential for various NLO application

Polymorphism in SmSc3(BO3)4: Crystal structure, luminescent and SHG properties

Low temperature C2/c and high temperature P321 modifications of SmxSc4-x (BO3)4 solid solutions were grown from LiBO2eLiF flux. These borates have typical luminescence for Sm3þ containing crystals with the two strongest peaks at 602 and 645 nm, which correspond to 4G5∕2 / 6H7∕2, 6H5∕2 electron transitions. In addition, the compounds were characterized by IR and Raman spectroscopy. SHG intensity for trigonal modification was found to be three times higher than that of KDP revealing its high potential for various NLO applications