Home | Contact | Sitemap | Directory | CAS | 中文
About Us News Research Scientist International Cooperation Education & Training Join Us Societies Papers Resources Links
Location: Home>Research>Research Progress
  • Research Divisions
  • Research Progress
  • Achievements
  • Research Programs
  • Supporting System
  • Researchers Synthesize a Novel Nonlinear Optical Lead Polyphosphate with Short Deep-UV Cutoff Edge
    Update time: 2016-12-01
    Text Size: A A A

    Nonlinear optical (NLO) material is one of the important parts of solid-state lasers. It is largely used in laser frequency conversion, optical parameter oscillators, other optical and photonic devices.

    Designing and synthesizing a deep UV NLO material requires crystallographic non-centrosymmetry, a wide UV transparency range, a large second-harmonic generating coecient, moderate birefringence, chemical stability and resistance to laser damage, and ease in the growth of large high-quality single crystals. For example, β-BaB2O4, LiB3O5 and CsLiB6O10 are successful example of NLO material. Recently, metal phosphates have attracted considerable interests for designing new DUV NLO materials.  

    A research group led by Prof. PAN Shilie at Xinjiang Technical Institute of Physics & ChemistryXTIPCof Chinese Academy of Sciences developed three new NLO crystals  APb2(PO3)5 (A = K, Rb and Cs).

    The three compounds are isostructural and belong to the non-centrosymmetric space group of Pn (No. 7). The structures of APb2(PO3)5 (A = K, Rb and Cs) exhibit a 3D network which consists of the PbOn (n = 6, 8), KO7/RbO8/CsO10 and PO4 units.  

    Researchers found UV-vis-NIR transmittance spectrum result shows that KPb2(PO3)5 has a short deep-UV cuto edge of 177 nm. It is the shortest UV cut-o edge among Pb-containing NLO crystals.

    Second harmonic generation (SHG) result indicate that KPb2(PO3)5 and RbPb2(PO3)5 are display moderate powder SHG intensities (0.5 × KDP and 0.3× KDP, respectively) in type I phase matching behaviors. Compared with RbBa2(PO3)5, KPb2(PO3)5 has a noticeable enhancement in birefringence (experimental value of 0.03 at 589.3 nm).  

    To better understand the blue-shift mechanism and enhancement of birefringence in KPb2(PO3)4, researchers employed the theoretical calculations by density functional theory.

    As a result, there is almost no hybridization between Pb-6p and O-2p orbitals at the top of valence bands, and therefore, the stereochemistry activity of the lead atom in KPb2(PO3)5 is weak according to the stereochemistry activity mechanism, which causes a blue-shift of the band gap in KPb2(PO3)5. 

    The result was published in J. Mater. Chem. C as a front cover. This article is part of themed collection: 2016 Journal of Materials Chemistry C Hot Papers. 

    This work was supported by the National Natural Science Foundation of China. 

    Figure1:The DUV transmittance spectrum and the photograph of the KPb2(PO3)5 crystal plate. (b) NLO properties of KPb2(PO3)5 and RbPb2(PO3)5 with commercial KDP as a reference(Image by XTIPC)

    Figure 2:The front cover of the article(Image by XTIPC)


    Prof.PAN Shilie 


    Xinjiang Technical Institute of Physics & Chemistry,CAS 

    Copyright © The Xinjing Technical Institute of Physics & Chemistry.CAS,All Right Reserved