Large nonlinear optical effect in tungsten bronze structures via Li/Na cross-substitutions
Shihang Chu1, Kun Lin1, Tao Yang1
1Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China. kunlin@ustb.edu.cn xing@ustb.edu.cn.
Abstract:
By a simple cross-substitution of A-site Li/Na in tetragonal tungsten bronze (TTB) structures, we successfully synthesized a new niobate compound, Pb2.15(Li0.25Na0.75)0.7Nb5O15, with a superstructure. This compound exhibits a strong second harmonic generation (SHG) up to ∼47 × KDP. The large SHG response is related to strengthened local distortion, manifesting cross-substitution as a possibly general route to improve the NLO effect in stiff and low symmetric structures.


