Local moment formation and resistivity minima in coal alloys

G. R. Caskey, D. J. Sellmyer

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Measurements of electrical resistivity, thermoelectric power, and magnetoresistance have been made from 1.4° to 300°K in alloys of 48%-57% cobalt in aluminum. At the equiatomic composition, CoAl has the CsCl structure. Resistance minima were observed in the vicinity of 30°K for cobalt concentrations between 50.4% and 51.5%. Below the resistance minima there is a temperature region where the dependence is approximately logarithmic before it saturates at about 1.4°K. The depth of the minima [ρ(1. 4°K)-ρ(Tmin)] and the thermopower at 4.2°K both show rather sharp peaks as a function of concentration in the vicinity of 50.5% cobalt. The magnetoresistance of the samples showing minima is negative or T<Tmin and its magnitude increases with field up to 150 kG. These results and earlier susceptibility measurements for this system are discussed in terms of several current theories of the electronic effects of magnetic impurities in metals.

Original languageEnglish (US)
Pages (from-to)1476-1477
Number of pages2
JournalJournal of Applied Physics
Volume40
Issue number3
DOIs
StatePublished - Dec 1 1969

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coal
moments
electrical resistivity
cobalt
aluminum
magnetic permeability
impurities
electronics
metals
temperature

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Local moment formation and resistivity minima in coal alloys. / Caskey, G. R.; Sellmyer, D. J.

In: Journal of Applied Physics, Vol. 40, No. 3, 01.12.1969, p. 1476-1477.

Research output: Contribution to journalArticle

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