Bulk crystal growth of congruent MgO-doped LiNbO3 crystal with stoichiometric structure and its second-harmonic-generation properties

Abstract A new LiNbO 3 bulk crystal has been grown by doping with MgO (cs-MgO:LN; Li 2 O:Nb 2 O 5 :MgO=45.30:50.00:4.70, (Li 0.906 Mg 0.047 V Li 0.047 )NbO 3 ), which successfully has the congruent point coinciding with the stoichiometric point. Its second-harmonic-generation (SHG) properties were evaluated. It was found that cs-MgO:LN has a much more homogeneous composition leading to uniform in-plane distribution of the non-critical phase-matching wavelength than the conventional LiNbO 3 crystals such as congruent LiNbO 3 (c-LN), stoichiometric LiNbO 3 (s-LN), and MgO-doped congruent LiNbO 3 (5MgO:LN). This homogeneity arose from the observation that none of the solute components including ionic species were segregated at the interface during growth. The SHG conversion efficiency of cs-MgO:LN is comparable to those of s-LN and 5MgO:LN.