ENERGY-STATE OF ND3+ DOPED IN BARIUM SODIUM NIOBATE CRYSTALS

Nd-doped barium sodium niobate (Ba2Na)(1-x)NdxNb5O15 (BNN:Nd), with x = 0.025 and a Curie temperature of 537 +/- 2 degrees C, crystallizes w ith a filled tungsten bronze-type structure in the tetragonal system. The lattice constants are a = b = 1.2446(1) and c = 0.3991(1) nm at ro om temperature. Then are two formulas per unit cell. The five typical deep energy levels, formed by the Nd3+ ions doped in the A1 and A2 sit es, are 2.36, 2.12, 1.68, 1.55, and 1.43 eV. Investigating the green a nd yellow second-harmonic generation shows that the BNN:Nd crystal can be expected as a useful material for the green, especially for the ye llow laser radiation at room temperature. (C) 1998 American Institute of Physics.