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Abstract: A single crystal of BaCaBO3F (BCBF) has been grown by the Czochralski pulling method in air. This compound was investigated for nonlinear optical applications especially in the ultraviolet. This BCBF material has a hexagonal structure with P6¯2m space group (Z=3) [D.A. Keszler, A. Akella, K.I. Schaffers, T. Alekel, Mater. Res. Soc. Symp. Proc. 329 (1994) 15]: its cell parameters are a=9.0489(8)Å and c=4.3257(4)Å. Its basic structural unit is [BO3]3− [D.A. Keszler, A. Akella, K.I. Schaffers, T. Alekel, Mater. Res. Soc. Symp. Proc. 329 (1994) 15] group. The UV absorption edge was measured at 210nm. The refractive indices were measured by the minimum deviation technique and fitted to the Sellmeier equations. In this article, second harmonic generation (SHG) and third harmonic generation (THG) phase-matching angle calculations are discussed. [Copyright &y& Elsevier]

Abstract: Single crystals of BaNaB9O15 (BNBO) have been grown by the Czochralski pulling method in air. This compound was investigated for nonlinear optical applications and was expected to exhibit an extended transparency window in the ultraviolet. The transmission spectrum of the crystal obtained is reported. The refractive indices were measured by the minimum deviation technique and fitted to the Sellmeier equations. The phase matching (PM) angle for type I SHG of 1064nm Nd:YAG laser was calculated to be θ=58.0°. Because BNBO possesses a very weak effective nonlinear optic coefficient and admits neither third-harmonic generation (THG) nor FHG of 1064nm laser, it is not interesting as a nonlinear material for UV light generation. [Copyright &y& Elsevier]

Abstract: The vertical conductivity of the p-Al0.11Ga0.89N/GaN SLs has been measured and calculated. The measured result (1.35×10−5 Scm−1) is in good agreement with the calculated result (2.26×10−5 Scm−1), indicating that the adoption of Fermi–Dirac distribution and sequential tunneling model in our calculation is very plausible. As a result, it is suggested that in p-AlGaN/GaN SLs the Fermi–Dirac distribution need to be considered in calculation related to hole distribution. [Copyright &y& Elsevier]