J. Phys. Colloques
Volume 49, Numéro C8, Décembre 1988Proceedings of the International Conference on Magnetism
|Page(s)||C8-2087 - C8-2092|
J. Phys. Colloques 49 (1988) C8-2087-C8-2092
µSR STUDIES OF HIGH TC SUPERCONDUCTIVITYY. J. Uemura1, B. J. Sternlieb1, D. E. Cox2, V. J. Emery2, A. Moodenbaugh2, M. Suenaga2, J. H. Brewer3, J. F. Carolan3, W. Hardy3, R. Kadono3, J. R. Kempton3, R. F. Kieff3, S. R. Kreitzman3, G. M. Luke3, P. Mulhern3, T. Riseman3, D. L. Williams3, B. X. Yang3, W. J. Kossler4, X. H. Yu4, H. Schone4, C. E. Stronach5, J. Gopalakrishnan6, M. A. Subramanian6, A. W. Sleight6, H. Hart7, K. W. Lay7, H. Takagi8, S. Uchida8, Y. Hidaka9, T. Murakami9, S. Etemad10, P. Barboux10, D. Keane11, V. Lee12 et D. C. Johnston13
1 Department of Physics, Columbia University, New York, NY 10027, U.S.A.
2 Brookhaven National Laboratory Upton, New York 11973, U.S.A.
3 TRIUMF and Univ. of British Columbia, Vancouver, B.C., V6T 2A3, Canada
4 College of William and Mary, Williamsburg, Virginia 23185, U.S.A.
5 Virginia State University, Petersburg, Virginia 23803, U.S.A.
6 Du Pont Experimental Station, Wilmington, Delaware 19898, U.S.A.
7 G.E. Corporate Research and Development, Schenectady, New York 12301, U.S.A.
8 University of Tokyo, Hongo, Tokyo 113, Japan
9 NTT Optoelectronics laboratory, Tokai, Ibaraki 319-11, Japan
10 Bell Communications Research, Red Bank, New jersey 07701, U.S.A.
11 IBM T. J. Watson research Center, Yorktown Heights, New York 10598, U.S.A.
12 IBM Almaden Research Center, San Jose, California 95120, U.S.A.
13 Ames Laboratory (USDOE), Ames, Iowa 50011, U.S.A.
Recent progress of our µSR measurements on high-TC and related systems is presented. Static magnetic order has been found and studied in La2CuO4, (La2-xSrx)CuO4, YBa2Cu3Ox, YBa2 (Cu3-xCox) O7, as well as in Bi2Sr2YCu2O8. No magnetic order was found in the 3-dimensional systems BaBiO3, Ba(Pb0.1Bi0.9) O3, and (BaK) BiO3 above T = 10 K. The anisotropy of the magnetic field penetration depth λ has been observed by using a c-axis alligned sintered pellet specimen of YBa2Cu3O7. The temperature dependence of λ|| (for c || Hext) indicates isotropic superconducting energy gap without any anomalies. Based on the muon spin relaxation rate σ observed in (random) pellet specimens of various high-TC superconductors, we found a linear relation between TC and σ α 1/λ2 α ns/m*, which suggests a high energy scale of superconducting coupling. Deviations from this linear relation are seen for samples with large carrier concentrations ns.