Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-10T09:03:25.471Z Has data issue: false hasContentIssue false
  • English
  • Français

Transport Properties of Granular Nix(SiO2)100−x Thin Films

Published online by Cambridge University Press:  28 February 2011

John R. Beamish ,
B.M. Patterson  and
K.M. Unruh
John R. Beamish
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716
B.M. Patterson
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716
K.M. Unruh
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716
Get access

Abstract

We have studied the electrical transport behavior of sputter deposited Nix(SiO2)100−x thin films between room temperature and 100 mK and, at selected temperatures, in applied magnetic fields up to 6 T. As the Ni concentration x is reduced, the resistivity increases systematically. At a Ni concentration (nominal) of about x–70 atomic percent (38 volume percent) the room temperature coefficient of resistivity changes sign. For Ni concentrations greater than 70 percent the resistance first decreases with temperature then increases logarithmically at, low temperatures. This increase becomes smaller and the resistivity minimum moves to progressively lower temperatures as the Ni concentration increases. In films with less than x–70 percent Ni, the resistivity has a temperature dependence of the form ρ(T)–ρo exp \(To/T)α] between room temperature and about 5 K. The exponent a is about 1/2 and To increases with decreasing Ni content. Below 1 K, however, the resistivity increases much less rapidly, with a temperature dependence independent of Ni concentration. In all films the magnetoresistance is small and negative.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 195: Symposium S – Physical Phenomena in Granular Materials , 1990 , 129
Copyright
Copyright © Materials Research Society 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Abeles, B., Sheng, P., Coutts, M.D. and Arie, Y., Adv. Phys. 24, 407 (1975); R.W. Simon, B.J. Dalrymple, D. Van Vechten, W.W. Fuller and S.A. Wolf, Phys. Rev. B36, 1962 (1987).Google Scholar
2.For reviews of experimental and theoretical work, see Bergmann, G., Phys. Rep. 107, 1 (1984); P.A. Lee and T.V. Ramakrishnan, Rev. Mod. Phys. 57, 287 (1985).Google Scholar
3. Efros, A.L. and Schklovskii, B.I., J. Phys. C: Solid State Physics 8, L49 (1975); O. Entin-Wohlman, Y. Gefen and Y. Shapira, J. Phys. C: Solid State Phys. 16, 1161 (1983).Google Scholar
4. Gershenfeld, N.A., VanCleve, J.E., Webb, W.W., Fisher, H.E., Fortune, N.A., Brooks, J.S. and Graf, M.J., J. Appl. Phys. 64, 4760 (1988).Google Scholar