Abstract
A direct observation of the grain-boundary phases for several well-characterized hot-pressed PbMo6S8 samples were made by Auger electron spectroscopy. The surface elemental concentrations are completely different when compared to its bulk composition. The thickness of this altered composition is in the range 100–200 Å gradually increasing with increase in hotpressing temperature. Also, evidence of segregation of impurities, such as carbon and SiOx, to the grain-boundaries were noticed for some of the samples. Calorimetric experiments show a continuous broadening and a reduction in amplitude of the specific heat anomaly atT c . This in terms of superconducting volume fraction indicates aT c distribution in the range 9–15 K. Such an observation can be related to the local inhomogeneities with respect to the ternary composition, i.e., a deviation from ideal stoichiometry, PbMo6S8. The results are discussed in conjunction with X-ray diffraction, scanning electron microscope, and energy dispersive X-ray analysis. By considering the grain-boundary phases and the calorimetric observation of inhomogeneities, a plausible explanation is given for the low critical current densities in these materials.
Similar content being viewed by others
References
Proc. Int'l Workshop on Chevrel-Phase Superconductors, Hôtel de Chavanne-de-Bogis, Switzerland (1991) pp. 1–79
Ø. Fischer, B. Maple (eds.):Superconductivity in Ternary Compounds I, II, Topics Curr. Phys. Vols. 32, 34 (Springer, Berlin, Heidelberg 1982)
See for example: L. Le Lay, T.C. Willis, D.C. Larbalestier: Appl. Phys. Lett.60, 775 (1992);
D. Cattani, J. Cors, M. Decroux, Ø. Fischer: IEEE TM-27, 950 (1991);
H. Yamasaki, M. Umeda, Y. Kimura, S. Kosaka IEEE TM-27, 1112 (1991);
G. Rimikis, W. Goldaker, W. Specking, R. Flükiger: IEEE TM-27, 1116 (1991)
D.W. Capone II, D.G. Hinks, D.L. Brewe: J. Appl Phys.67, 3043 (1990)
L. Le Lay, P. Rabiller, R. Chevrel, M. Sergent, T. Verhaege, J.C. Vallier, P. Genevey: Adv. Cryog. Eng.36, 3298 (1990)
M.O. Rickel, T.G. Togonidze, V.I. Tsebro: Sov. Phys.-Solid State28, 1496 (1986)
P. Selvam, D. Cattani, J. Cors, M. Decroux, A. Junod, Ph. Niedermann, S. Ritter, Ø. Fischer, P. Rabiller, R. Chevrel, L. Burel, M. Sergent: Mater. Res. Bull.26, 1211 (1991)
P. Selvam, D. Cattani, J. Cors, M. Decroux, A. Junod, Ph. Niedermann, S. Ritter, Ø. Fischer, P. Rabiller, R. Chevrel: J. Appl. Phys.72, 4232 (1992)
J.D. Jorgensen, D.G. Hinks: Solid State Commun.53, 289 (1985)
J.D. Jorgensen, D.G. Hinks, G.P. Felcher: Phys. Rev. B35, 5365 (1987)
C. Meingast, W. Goldacker, U. Wildgruber: In [1]Proc. Int'l Workshop on Chevrel-Phase Superconductors, Hôtel de Chavanne-de-Bogis, Switzerland (1991) p. 7
M. Francois, K. Yvon, D. Cattani, and M. Decroux, R. Chevrel, M. Sergent, S. Boudjada, Th. Wrobleswski: J. Appl. Phys. 75, 423 (1994)
P. Selvam, D. Cattani, J. Cors, M. Decroux, Ph. Niedermann, Ø. Fischer: In [1]Proc. Int'l Workshop on Chevrel-Phase Superconductors, Hôtel de Chavanne-de-Bogis, Switzerland (1991) p. 31
M. Decroux, P. Selvam, J. Cors, B. Seeber, Ø. Fischer, P. Rabiller, R. Chevrel: IEEE Trans. AS-3, 1502 (1993)
M. Decroux, D. Cattani, J. Cors, S. Ritter, Ø. Fischer: Physica B165&166, 1395 (1990)
R.W. Rollins, H. Kupfer, Z.W. Gey: J. Appl. Phys.45, 5392 (1974)
D. Cattani: Etude des densités de courant critique dans le composé PbMo6S8. Dissertation no. 2422, Université de Genève (1990)
L.E. Davis, N.C. MacDonald, P.W. Palmberg, G.E. Riach, R.E. Weber (eds.):Handbook of Auger Electron Spectroscopy (Physical Electronics, Eden Prairie, MN 1976)
J. Cors: Propriétés superconductrices sons champ magnetique du composé PbMo6S8 étudiées par chaleur spécifique. Dissertation no. 2456, Université de Genève (1990)
A. Junod, T. Jarlborg, J. Muller: Phys. Rev. B27, 1568 (1983)
D. Briggs, M.P. Seah (eds.):Practical Surface Analysis, 2nd edn., Vol. 1 (Wiley, Chichester 1990)
J. Derrien, M. Commandre: Surf. Sci.118, 32 (1982)
D.G. Hinks, J.D. Jorgensen, H.-C. Li: Phys. Rev. B51, 1911 (1983)
W. Goldaker, E. Seibt, G. Rimikis, R. Flukiger: InProc. 2nd Int'l Conf. on Modern Superconductivity towards Applications (IITT-Int'l, Paris 1990) p. 99
P. Selvam, D. Cattani, J. Cors, M. Decroux, Ph. Niedermann, S. Ritter, Ø. Fischer, L. Burel, R. Chevrel, P. Rabiller, M. Sergent: InProc. 3rd Int'l Conf. on Superconductivity—Materials, Physics and Applications (IITT-Int'l, Paris 1991), p. 157
G.L. Dorofejer, E.Y. Klimenko, S.V. Frolov, E.V. Nikulenkov, E.I. Plashkin, V.Y. Filkin: InProc. MT-9, Zurich, (1982) p. 564
P. Selvam, D. Cattani, J. Cors, M. Decroux, Ph. Niedermann, Ø.Fischer, R. Chevrel, T. Pech: IEEE Trans. AS-3, 1575 (1993)
P. Selvam, J. Cors, D. Cattani, M. Decroux, Ø. Fischer, E.W. Seibt: Appl. Phys. A (submitted)
R. Baillif, A. Dunand, J. Muller, K. Yvon: Phys. Rev. B47, 672 (1981)
R. Baillif, A. Junod, B. Lachal, J. Muller, K. Yvon: Solid State Commun.40, 603 (1981)
B. Lachal R. Baillif, A. Junod, J. Muller: Solid State Commun.45, 849 (1983)
S. Yamamoto, M. Wakihara, M. Taniguchi: Mater. Res. Bull.20 1493 (1985)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Selvam, P., Cors, J., Decroux, M. et al. Surface and bulk properties of hot-pressed PbMo6S8 superconductor studied by Auger electron spectroscopy and calorimetry. Appl. Phys. A 60, 459–465 (1995). https://doi.org/10.1007/BF01538770
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01538770