Abstract
The profiles of the magnetic induction near the surface of cylindrical niobium samples were measured by the method of differential susceptibility in minor hysteresis loops. The flux density gradient near the surface generally is considerably higher than in the bulk. This may be interpreted in terms of a surface barrier or of a surface pinning force. The experimental results can be summarized as follows: (1) Surface pinning always increased with surface roughness. (2) When the surface was polished the barrier was only observed in a plastically deformed sample. (3) The influence of the surface seems to extend down to a depth of some tenth of a millimeter.
Similar content being viewed by others
References
A. M. Campbell and J. E. Evetts, Adv. Phys. 21, 199 (1972).
H. Ullmaier, Irreversible Properties of Type-II Superconductors (Springer Tracts in Modern Physics, Vol. 76; Springer-Verlag, Berlin, 1975).
R. Labusch, Cryst. Latt. Def. 1, 1 (1969).
R. Schmucker and E. H. Brandt, Phys. Stat. Sol. (b) 79, 479 (1977).
C. P. Bean, Phys. Rev. Lett. 8, 250 (1962).
H. A. Ullmaier and W. F. Gauster, J. Appl. Phys. 37, 4519 (1966).
C. P. Bean and J. D. Livingston, Phys. Rev. Lett. 12, 16 (1964).
W. I. Dunn and P. Hlawiczka, Brit. J. Appl. Phys. 1, 1469 (1968).
J. Friedel, P. G. de Gennes, and J. Matricon, Appl. Phys. Lett. 2, 119 (1963).
G. Zerweck, Phil. Mag. 27, 197 (1973).
G. Zerweck, Rev. Bras. Fis. 8, 225 (1978).
A. Das Gupta, W. Gey, J. Halbritter, H. Küpfer, and J. A. Yasaitis, J. Appl. Phys. 47, 2146 (1976).
A. Bodmer, Dissertation, Universität Stuttgart (1976).
I. Adaktylos, E. Schachinger, and H. W. Weber, J. Low Temp. Phys. 23, 533 (1977).
H. R. Hart and P. S. Swartz, Phys. Rev. 156, 403 (1967).
J. Lowell, J. Phys. C 2, 372 (1969).
A. Das Gupta and E. J. Kramer, Phil. Mag. 26, 776 (1972).
D. D. Morrison and R. M. Rose, J. Appl. Phys. 42, 2322 (1971).
D. Eckert and A. Handstein, Phys. Stat. Sol. (a) 37, 171 (1976).
M. S. Duesbery, R. A. Foxall, and P. B. Hirsch, J. Phys. Radium. 27, C3–193 (1966).
O. F. de Lima, G. Zerweck, and A. S. Brito, J. Low Temp. Phys. 32, 717 (1978).
G. J. Van Gurp and D. J. Van Oojen, J. Phys. Radium 27, C3–51 (1966).
H. C. Freyhardt, Phil. Mag. 23, 345 (1971).
W. Schwarz and J. Halbritter, J. Appl. Phys. 48, 4618 (1977).
K. A. Jones and R. M. Rose, Acta Met. 24, 45 (1976).
E. J. Kramer, J. Appl. Phys. 44, 1360 (1973).
H. Mughrabi, Phys. Stat. Sol. 39, 317 (1970).
H. Hahn and H. J. Halama, J. Appl. Phys. 47, 4629 (1976).
J. Pearl, J. Appl. Phys. 37, 4139 (1966).
F. Irie and K. Yamafuji, J. Phys. Soc. Jpn 23, 255 (1967).
E. H. Brandt, Phil. Mag. B-37, 293 (1978).
E. H. Brandt, Phys. Stat. Sol. 35, 1027 (1969).
E. H. Brandt, private communication.
Author information
Authors and Affiliations
Additional information
Work supported by FAPESP.
Rights and permissions
About this article
Cite this article
Brito, A.S., Zerweck, G. & de Lima, O.F. High critical flux density gradients near the surface of superconducting niobium. J Low Temp Phys 36, 33–46 (1979). https://doi.org/10.1007/BF00174910
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00174910