Abstract
In an attempt to understand the role of stoichiometry in controlling the transport properties of the system YBa2Cu3O7−x (0 < x < 1), we have performed electrical conductivity (σ) and thermoelectric power (Q) measurements, in situ, as a careful function of temperature, oxygen partial pressure, and oxygen stoichiometry.
In the low temperature orthorhombic phase, a continuous transition from semiconducting to metallic conduction was observed as temperature decreases and Po2 increases as a result of exothermic generation of holes. Both the magnitude of Q and the Po2 dependence of σ and Q confirm the p-type nature of the carriers. In the high temperature tetragonal phase a p-n semiconducting transition is detected which shifts to higher temperature as the Po2 is increased. Based on these results and results of measurements performed as a function of temperature for fixed values of x, we conclude that the n-type contribution is a result of the disproportionation of Cu1+ to Cu0 and Cu2+ which is characterized by an energy of 1.24 eV. A preliminary defect model is proposed which provides a framework for understanding the Po2 dependence of σ and Q.
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References
M.P. Pechini, U.S. Patent 3,330,697 (11 July 1967).
G.M. Choi and H. L. Tuller, J. Am. Ceram. Soc. 71 201 (1988).
H.L. Tuller and A.S. Nowick, J. Phys. Chem. Sol. 38 859 (1977).
G.M. Choi, H.L. Tuller, and M.-J. Tsai, in Proc. Svmp. High Temperature Superconductors, (MRS Symp. Proc. V.99), eds., M.W. Brodsky, R.C. Dynes, K. Kitizawa, and H. L. Tuller, Mat. Res. Soc., Pittsburgh, PA (1988), p. 141.
K. Kishio, J. Shimoyama, T. Hasegawa, K. Kitazawa, and K. Fueki, Jpn. J. Appl. Phys. 26 L1054 (1987).
H.M. O’Bryan and P.K. Gallagher, Adv. Cer. Mat. 2 [3B] 640 (1987).
H.I. Yoo, ‘High Temperature Transport Properties of the High Tc Superconductor Y1Ba2Cu3OX, J. Mat. Res., recently submitted.
D. Ahuja, S.E. Dorris, M.Y. Su, Q. Robinson, D.L. Johnson, and T.O. Mason in Proc. Symp. High-Temperature Superconductors (MRS Symp. Proc. Vol. 99), eds. M.W. Brodsky, R.C. Dynes, K. Kitizawa, and H.L. Tuller, Mat. Res. Soc., Pittsburgh, PA (1988) p. 467.
D.W. Murphy, S.A. Sunshine, P.K. Gallagher, H.M. O’Bryan, R.J. Cava, B. Batlogg, R.B. van Dover, L.F. Schneemeyer, and J.M. Zahurak, in Proc. Symp. Chemistry of High-Temperature Superconductors (ACS Symp. Sec. 351), eds., D.L. Nelson, M.S. Whittingham, and T.F. George, Am. Chem. Soc., Washington D.C. (1987), p. 181.
S. Sageev Grader, P.K. Gallagher, and E.M. Gyorgy, Appl. Phys. Lett. 51 5 (1987).
J.S. Blakemore, Solid State Physics, 2nd Edition, Cambridge Univ. Press, Cambridge, England, 1985, p. 319.
E.K. Chang, D.J.L. Hong, A. Mehta, and D.M. Smyth, Mat. Lett. 6 251 (1988).
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© 1989 Kluwer Academic Publishers
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Choi, G.M., Tuller, H.L., Tsai, MJ. (1989). Defects and Transport in YBa2 Cu3 O7 − x . In: Nowotny, J., Weppner, W. (eds) Non-Stoichiometric Compounds. NATO ASI Series, vol 276. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-0943-4_31
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DOI: https://doi.org/10.1007/978-94-009-0943-4_31
Publisher Name: Springer, Dordrecht
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