Magnetic Field Dependence of the Specific Heat of Some High-Tc Superconductors
Measurements of specific heat, C, were made on samples of La2CuO4−y (La1), La1.85M0.15CuO4−y (Ca1, Sr1, Sr2, Ba1 and Ba2) and YBa2Cu3O9−y (Y1). Meissner effect measurements were made in 12.5G. The high-temperature onset of a change in magnetic susceptibility, χ, was taken as Tc, and the transition width, ΔTc, as the temperature interval of the 10–90% change in χ. Calculation of the fractional Meissner effect, −4πχV, was based on the total sample volume, with χV corrected for demagnetizing effects. Figure 1 is a plot of −4πχV vs T.
KeywordsEntropy Hull Germanium Maki La2CuO4
Unable to display preview. Download preview PDF.
- 2.cf.: G.R. Stewart and B.L. Brandt, Phys. Rev. B29, 3908 (1984); J.F. DaSilva, N.W.J. Van Duykern and Z. Dokoupil, Physica 32, 1253 (1966); R. Radebaugh and P.H. Keesom, Phys. Rev. 149, 217 (1966); F.J. Morin, J.P. Maita, H.J. Williams, R.C. Sherwood, J.H. Wernick and J.E. Kunzler, Phys. Rev. Lett. S9 275 (1962)Google Scholar
- 3.cf.: T.P. Orlando, K.A. Delin, S. Foner, E.J. McNiff, Jr., J.M. Tarascon, L.H. Greene, W.R. McKinnon and G.W. Hull, Phys. Rev. B35, 5347 (1987); D.K. Finnemore, R.N. Shelton, J.R. Clem, R.W. McCallum, H.C. Ku, R.E. McCarley, S.C. Chen, P. Klavins and V. Kagan, Phys. Rev. B35, 5319 (1987).CrossRefGoogle Scholar
- 4.P.W. Anderson, preprint.Google Scholar
- 5.B. Batlogg, A.P. Ramirez, R.J. Cava, R.B. van Dover and E.A. Rietman, Phys. Rev. B35, 5340 (1987); B.D. Dunlap, M.V. Nevitt, M. Sloski, T.E. Klippert, Z. Sungoila, A.G. McKale, D.W. Capone, R.B. Poeppel and B.K. Flandermeyer, preprint; M. Decroux, A. Junod, A. Bezinge, D. Cattani, J. Cors, J.L. Jorda, A. Stettler, M. Francois, K. Yvon, 0. Fischer and J. Muller, preprint.Google Scholar