RBa2Cu3O7−δ (R = rare earth) high-Tc magnetic superconductors

✍ Scribed by M.B. Maple; Y. Dalichaouch; J.M. Ferreira; R.R. Hake; B.W. Lee; J.J. Neumeier; M.S. Torikachvili; K.N. Yang; H. Zhou; R.P. Guertin; M.V. Kuric

• Publisher: Elsevier Science
• Year: 1987
• Weight: 572 KB
• Volume: 148
• Category: Article
• ISSN: 0378-4363
• DOI: 10.1016/0378-4363(87)90181-1

✦ Synopsis

Electrical resistivity p, magnetization M, and specific heat C measurements have been made on polycrystalline RBaefu307_ ~ compounds (R = Y or a rare earth element) which, except for R = Ce, Pr and Tb, exhibit superconductivity with T~ ~-90 K. Measurements of C(T) below T c reveal (1) a contribution linear in T and Debye and Einstein lattice contributions for R = Y, and (2) electronic Schottky anomalies due to crystalline electric field effects and magnetic ordering for many R ions with partially-filled 4f electron shells. Measurements of p(T, H) and M(T, H) yield upper critical field slopes near T~ of ~<3 T/K and critical current densities ~<3.5 × 10 a A/cm 2 at 4.2 K in zero field.