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Magnetic behaviour in Dy(1-x)Mm(x)Co2 compounds
G Srinivas1, M Ellerby, N T Skipper
1London Centre For Nanotechnology, Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London WC1H 0AH, UK. gsrini@seas.upenn.edu
Summary
Mischmetal (Mm) substitution in DyCo(2) compounds significantly alters magnetic properties. Increasing Mm content reduces magnetic ordering temperature, saturation magnetization, and cobalt moment, shifting the magnetic transition order.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Dysprosium cobalt (DyCo(2)) compounds exhibit interesting magnetic behaviors.
- Understanding the impact of substitutions on these properties is crucial for materials development.
- Mischmetal (Mm) is a rare-earth alloy often used as a substitute in magnetic materials.
Purpose of the Study:
- To investigate the magnetic behavior of Dy(1-x)Mm(x)Co(2) compounds.
- To analyze the effect of mischmetal (Mm) substitution on magnetic ordering and transitions.
- To determine the influence of Mm on the cobalt sublattice magnetization.
Main Methods:
- Temperature and field dependence of magnetization (M-T and M-H) measurements were performed.
- Arrott plots (M(2) versus H/M) were utilized to analyze magnetic transitions.
- Compositional series from x = 0 to 0.5 were studied.
Main Results:
- A strong composition-dependent irreversibility was observed below the magnetic ordering temperature (T(C)).
- The magnetic transition changed from first-order in DyCo(2) to second-order in Dy(0.5)Mm(0.5)Co(2).
- Mischmetal substitution led to a reduction in T(C), saturation magnetization, and the cobalt moment.
Conclusions:
- Mischmetal substitution significantly modifies the magnetic characteristics of DyCo(2) compounds.
- The observed changes are attributed to variations in the cobalt sublattice moments.
- The study provides insights into tuning magnetic properties through controlled substitution.
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