Journal of Low Temperature Physics

, Volume 90, Issue 3–4, pp 181–204 | Cite as

Magnetic ordering in CeCu6−xAu x single crystals: Thermodynamic and transport properties

  • H. G. Schlager
  • A. Schröder
  • M. Welsch
  • H. v. Löhneysen
Article

Abstract

We report on measurements of the magnetizationM, specific heatC, resistivity ρ, and magnetoresistivity of CeCu 6−x Au x single crystals (x=0.3 and 0.5) grown by the Czochralski method. Antiferromagnetic ordering is observed inM andC for temperatures less thanTN=0.48 K (x=0.3) and 0.95 K (x=0.5), similar to the ordering temperatures found previously for polycrystalline samples. As a function of magnetic fieldB, M(B) andC(T, B) are strongly anisotropic, with the easy axis along the crystallographicc direction (orthorhombic notation) as for pure CeCu 6 . For large magnetic fields where the magnetic ordering is suppressed, the specific heat can be described by the resonance-level model suggestive of a single-ion Kondo effect, similar to CeCu 6 where for largeB the short-range magnetic correlations are suppressed. The averaged Kondo temperature as determined from a number of properties decreases with increasingx, withTK=4.0 K forx=0.3 and 3.0 K forx=0.5, compared to 5.8 K forx=0. The magnetoresistivity shows a negative contribution arising from incoherent Kondo scattering and a positive contribution associated with the magnetic order.

Keywords

Magnetic Field Magnetic Material Transport Property Positive Contribution Polycrystalline Sample 

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • H. G. Schlager
    • 1
  • A. Schröder
    • 1
  • M. Welsch
    • 1
  • H. v. Löhneysen
    • 1
  1. 1.Physikalisches Institut der Universität KarlsruheKarlsruheGermany

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