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Tunable magnetic orders in CePd2As2-xPx.
1Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, People's Republic of China.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|December 21, 2013
Summary
Researchers synthesized CePd2As2-xPx compounds, tuning their magnetic properties from antiferromagnetic to ferromagnetic. This tunability in magnetic ground state offers insights into quantum critical behavior in these materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Ternary intermetallic compounds with ThCr2Si2-type structure are known for diverse electronic and magnetic properties.
- Cerium-based intermetallics often exhibit complex magnetic phenomena due to the localized 4f electrons.
Purpose of the Study:
- To synthesize polycrystalline CePd2As2-xPx compounds and investigate their physical properties.
- To explore the evolution of magnetic ground states (antiferromagnetic to ferromagnetic) with varying As/P substitution.
- To study the impact of substitution on magnetic transition temperatures and metamagnetic behavior.
Main Methods:
- Polycrystalline sample synthesis.
- Powder X-ray diffraction for structural characterization.
- Measurements of transport, magnetic, and thermodynamic properties as a function of temperature and magnetic field.
Main Results:
- CePd2As2-xPx crystallizes in the ThCr2Si2-type tetragonal structure.
- CePd2As2 shows antiferromagnetic (AFM) ordering at TN ≈ 15 K with a moderate Sommerfeld coefficient.
- Substitution of As by P tunes the magnetic ground state from AFM to ferromagnetic (FM), with Curie temperature (TC) reaching ≈ 28 K in CePd2P2.
- Metamagnetic transitions observed in As-rich samples disappear for x ≥ 0.4.
Conclusions:
- The study successfully demonstrates the tunability of magnetic ground states in CePd2As2-xPx by controlling the As/P ratio.
- The observed magnetic phase transitions and tunable properties suggest potential for exploring quantum critical phenomena.
- These findings contribute to the understanding of structure-property relationships in cerium intermetallic compounds.
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