New Study of Electrical Conductivity in Ni-Doped Non-Stoichiometric Lithium Tantalate

Abstract

Ceramics of Li_0.98-x Ta_1.004-x/5 O₃ solid solutions with 0 ≤ × ≤ 0.20 are studied by a new theoretical approach. From the experience, we have proposed the new vacancy models which are able to describe substitutional mechanism in Ni-doped lithium tantalate. Theoretical approach combined with generalised vacancy models allows us to establish a new expression of electrical conductivity which takes into account the defect structure of Ni-doped lithium tantalate. Calculation of the Curie temperature in Ni-doped non stoichiometric lithium tantalate reveals good correspondence with experimental results.

Keywords:

• Ni:LiTaO₃
• Structural materials
• Electrical conductivity
• Curie temperature
• Vacancy models

Acknowledgments

We gratefully acknowledge financial support from the Ministry of Higher Education and the National Center for Scientific Research and Technology.