Bulk periodic poled lithium niobate crystals doped with Er and Yb

Periodic poled lithium niobate crystals have been prepared by the Czochrals ki technique using a non-symmetrical temperature field. Er and Yb ions have been added to the melt in different concentrations and its effect on the f ormation of the periodical structures has been studied. The periodical doma in structures are improved for dopant concentrations lower than the solubil ity limit. The formation of the periodical domain structures is related wit h the dopant segregation coefficient value and with the temperature gradien t in the interface. (C) 1999 Elsevier Science B.V. All rights reserved.