Research on new frequency convesion crystal BABF for vacuum ultraviolet light generation

我们发现了一种新的非线性光学(NLO)硼酸铝酸盐BaAlBO_3F_2(BABF)晶体。用四轴X射线衍射法对其结构进行了表征。该材料属P6^^空间群，晶胞参数为a=4.8879(6)Å，c=9.403(1)Å，Z=2，是产生较大倍频系数、宽透明区域和中等双折射的理想结构模型。BABF的结构类似于KBE_2BO_3F_2(KBBF)，但其成分中不含有毒元素。BABF晶体比KBBF晶体更容易生长，生长周期相对较短。BABF晶体可以生长出尺寸为15×15×3.5 mm^3的晶体。BABF晶体具有良好的化学、力学和光学性能，但BABF晶体的质量有待提高，这方面的努力正在进行中。我们得到了一种透明的BABF晶体，用于测量它的线性和非线性光学性质。S的紫外吸收边很短(165 Nm)。BABF的粉末倍频效率约为KH_2PO_4(KDP)的两倍。计算了d_&lt；11&gt；(0.165 pm/V)和d_&lt；22&gt；(1.32 pm/V)。第1类倍频比杠杆收购高出约28%，第1类倍增比杠杆收购高出31%。结果表明，BABF是紫外光频率混频的极佳候选者。

We have discovered a new nonlinear optical (NLO) alumino-borate BaAlBO_3F_2 (BABF) crystal. Its structure has been characterized by 4-axis X-ray diffraction. BABF, the material, crystallizes in the space group P6^^with a = 4.8879(6) Å, c = 9.403(1) Å and Z = 2. BABF structure is an ideal structural model for producing larger SHG coefficients, wide transparent region and moderate birefringence. BABF has a structure similar to that of KBe_2BO_3F_2 (KBBF), but does not contain toxic elements in its composition. BABF crystal is easier grown than KBBF and the growth period of BABF are relative shorter than other nonlinear borate crystals. BABF crystal can be grown with dimensions of 15 x15 x 3.5mm^3. BABF crystal possesses good chemical and mechanical and optical properties, but the quality of BABF crystal needs to be improved and the effort in this direction is underway. We have obtained a transparent BABF crystal for the measurements of its linear and nonlinear optical properties. The UV absorption edge of BABF s very short (165nm). BABF was found to have powder second harmonic generation (SHG) efficiency about twice than that of KH_2PO_4 (KDP). The d_<11>(0.165pm/V) and d_<22> (1.32pm/V) were calculated. Type-1 SHG d_<eff> is about 28% higher than that of LBO and Type-1 THG d_<eff> is 31% higher than that of LBO. It exhibits that BABF is an excellent candidate for frequency mixing into the ultraviolet.