Electrical transport properties of gadolinium scandium gallium garnet

• Published in: The Journal of physics and chemistry of solids Vol. 46; no. 8; pp. 957 - 962
• Main Authors: Schwartz, K.B., Duba, A.G.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1985; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; defect structure; electrical conductivity; Electronic transport in condensed matter; Exact sciences and technology; garnets; GSGG; laser materials; Low-field transport and mobility; piezoresistance; mixed conduction; Physics; mixed conduction; electrical conductivity; laser materials; GSGG; defect structure; garnets; Electrical conductivity; Electronic conductivity; Very high temperature; Thermoelectric power; Ionic conductivity; Lanthanide Compounds; Experimental study; Gadolinium Gallium Scandium Oxides Mixed; Inorganic compound
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/0022-3697(85)90099-X

Electrical conductivity and thermoelectric power are measured on a single crystal of Gd 3.0Sc 1.8Ga 3.2O 12 (GSGG) between 1273 and 1673 K. The measurements are made both in air and in controlled atmospheres, and P O 2 varies from 10 −1.68 to 10 −5.6 MPa. The data indicate GSGG may well be a mixed conductor in this temperature and P O 2 range, with n-type electronic conductivity and ionic transport on the oxygen sublattice. Changes in temperature induce long-lived disequilibrium in electrical conductivity of GSGG (over 30 h at T < 1373 K) that can be explained by temperature dependent cation redistribution. The effective activation energy for equilibrium electrical conductivity is E a = 2.40 ± 0.05 eV, as opposed to values of E a between 1.8 and 2.2 eV during actual temperature changes. An additional contribution in the equilibrium E a, due to thermally activated cation redistribution, can account for the higher value seen.