| 摘要 |
A method of growing a single crystal of KTiOPO4 which is a nonlinear optical material is disclosed. Growth of the single crystal of KTiOPO4 is carried out by melting a KTiOPO4 material with a flux to produce a melt, then contacting a seed crystal to the melt, and by slowly cooling at a saturation temperature or below. At this time, molar fractions of K2O, P2O5 and TiO2 contained in the melt fall within a region surrounded by six points in a K2O-P2O5-TiO2 ternary phase diagram of A (K2O: 0.4150, P2O5: 0.3906, TiO2: 0.1944), B (K2O: 0.3750, P2O5: 0.3565, TiO2: 0.2685), C (K2O: 0.3750, P2O5: 0.3438, TiO2: 0.2813), D (K2O: 0.3850, P2O5: 0.3260, TiO2: 0.2890), E (K2O: 0.4000, P2O5: 0.3344, TiO2: 0.2656), and F (K2O: 0.4158, P2O5: 0.3744, TiO2: 0.2098). In addition, K15P13O40 or the same composition produced by melting is used as the flux, and the proportion of a KTiOPO4 element in a composition of the melt is prescribed to 83.5 to 90.0 mol%. The seed crystal is set so that a C axis is in a direction perpendicular to a melt surface. Then, the seed crystal contacted to the melt is rotated and slowly cooled. Thus, a single crystal of KTiOPO4 of single domain at the end of growth can be produced. <IMAGE> |
