Growth and characterization of BaGa4Se7 crystal

High-quality crystals of BaGa4Se7, a newly developed IR nonlinear optical (NLO) material, were obtained via the Bridgman-Stockbarger technique. The FWHM of the (002) peak rocking curve is about 0.008 degrees and the transmittance through a polished 2 mm thick (001) plate is around 65% over the wide range of 1-14 mu m. Various thermophysical properties were measured on crystals. The thermal expansion behavior in BaGa4Se7 does not exhibit strong anisotropy with alpha(a) = 9.24 x 10(-6) K-1, alpha(b) = 10.76 x 10(-6) K-1, and alpha(c) = 11.70 x 10(-6) K-1 along the three crystallographic axes. The thermal diffusivity/thermal conductivity coefficients measured at 298 K are 0.50(2) mm(2) s(-1)/0.74(3)W m(-1) K-1, 0.42(3) mm(2) s(-1)/0.64(4) W m(-1) K-1, 0.38(2) mm(2) s(-1)/0.56(4)W m(-1) K-1, along the a, b, c crystallographic axis respectively. In addition, the surface laser damage threshold was measured to be 557 MW/cm(2) using a Nd:YAG (1.064 mu m) laser under conditions of 5 ns pulse width, 1 Hz frequency, and D=0.4 mm spot size. (C) 2012 Elsevier B.V. All rights reserved.