Artículos de revistas
Low-field Magnetic Relaxation Study Of A Yba2cu3ox Single Crystal With H ∥ A-b Planes
Registro en:
Superconductor Science And Technology. , v. 10, n. 5, p. 284 - 289, 1997.
9532048
10.1088/0953-2048/10/5/004
2-s2.0-3943082697
Autor
Salem-Sugui Jr. S.
Alvarenga A.D.
Schilling O.F.
Sengupta S.
Institución
Resumen
We have measured magnetic relaxation M versus time in a twin-free single crystal of YBa2Cu3Ox for magnetic fields applied parallel to a-b planes. Magnetic relaxation is studied as a function of temperature (T) for a fixed field (H) and at a fixed T as a function of H. Long-time M versus t curves were mainly obtained for the partial field penetrating regime. All log M versus log t curves obtained in the partial-field regime present a kink at time t* separating two distinct regions. The kink gradually disappears as the applied field fully penetrates the sample. The value of t* is constant for all field values. Similar but more accentuated differences are observed when the effective activation energy U extracted from the data is plotted against M(t). A linear behaviour of U with M is observed in the full field penetrated regime. We estimate that the Bean penetration depth increases exponentially with H in the partial-field regime. We also determined the range of temperatures for which surface barriers are important at the initial stage of relaxation. 10 5 284 289 De Gennes, P.G., (1966) Superconductivity of Metals and Alloys, , New York: Benjamin Wollan, J.J., Hass, K.W., Clem, J.R., Finnemore, D.K., (1974) Phys. Rev. B, 10, p. 1874 Bean, C.P., (1962) Phys. Rev. Lett., 8, p. 250 Bean, C.P., (1964) Rev. Mod. Phys., 36, p. 31 Campbell, A.M., Evetts, J.E., (1972) Adv. Phys., 21, p. 199 Xu, M., Shi, D., (1990) Physica C, 168, p. 303 Xu, M., Shi, D., Umezawa, A., Vandervoort, K.G., Crabtree, G.W., (1991) Phys. Rev. B, 43, p. 13049 Shi, D., Salem-Sugui Jr., S., (1991) Phys. Rev. B, 44, p. 7647 Schnack, H.G., Griessen, R., (1992) Phys. Rev. Lett., 68, p. 2706 Weir, S.T., Nellis, W.J., Dalichaouch, Y., Lee, B.W., Maple, M.B., Liu, J.Z., Shelton, R.N., (1991) Phys. Rev. B, 43, p. 3034 Chikumoto, N., Konszykowksi, M., Motohira, N., Malozemoff, A.P., (1992) Phys. Rev. Lett., 69, p. 1260 Burlachkov, L., (1993) Phys. Rev. B, 47, p. 8056 Clem, J.R., (1974) Proc. 13th Conf. on Low Temperature Physics (LT13), 3, p. 102. , ed D D Timmerhaus, W J O'Sullivan and E F Hammel (New York: Plenum) Kopylov, V.N., Koshelev, A.E., Schegolev, I.F., Togonidze, T.G., (1990) Physica C, 170, p. 291 Konczykowski, M., Burlachkov, L., Yeshurun, Y., Holtzberg, F., (1991) Phys. Rev. B, 43, p. 13707 Burlachkov, L., Konczykowski, M., Yeshurun, Y., Holtzberg, F., (1991) J. Appl. Phys., 70, p. 5759 Xu, M., Finnemore, D.K., Crabtree, G.W., Vinokur, V.M., Dabrowski, B., Hinks, D.G., Zhang, K., (1993) Phys. Rev. B, 48, p. 10630 Alvarenga, A.D., Salem-Sugui Jr., S., (1994) Physica C, 235-240, p. 2811 Harshman, D.R., Schneemeyer, L.F., Waszczak, J.V., Aeppli, G., Cava, R.J., Batlogg, B., Rupp, L.W., Willians, D.L.I., (1989) Phys. Rev. B, 39, pp. R851 Maley, M.P., Willis, J.O., Lessure, H., McHenry, M.E., (1990) Phys. Rev. B, 42, pp. R2639 Salem-Sugui Jr., S., Shi, D., (1992) Phys. Rev. B, 46, p. 6618 Beasley, M.R., Labuch, R., Webb, W.W., (1969) Phys. Rev., 181, p. 682 Vinokur, V.M., Geshkenbein, V.B., (1992) Phys. Rev. Lett., 68, p. 2707