Magnetic Properties of Pyrochlore Ruthenate Nd₂Ru₂O₇ Studied by μSr

Abstract:

We investigated the magnetic properties of pyrochlore ruthenates, R₂Ru₂O₇, by using the muon spin relaxation (μSR) method. The appearance of a magnetically ordered state was confirmed below 145 K by observing the decrease in the initial asymmetry of the muon-spin polarization. This was due to a long-range ordering of Ru⁴⁺ spins. An additional anomaly in the μSR time spectrum was observed around 30 K. A part of the lost initial asymmetry was recovered and gradually decreases again with decreasing temperature below 30 K. This anomaly was supposed to be due to a magnetic ordering of Nd³⁺ spins which was coupled with ordered Ir moment via the 3d-4f exchange interaction.

• Periodical: Key Engineering Materials (Volume 860)
• Pages: 288-293
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.860.288
• Online since: August 2020
• Authors: Utami Widyaiswari, Hideaki Sakai, Kanji Inoue, Noriaki Hanasaki, Dita Puspita Sari, Budhy Kurniawan*, Isao Watanabe
• Keywords: Magnetic Ordering, Muon Spin Relaxation, Pyrochlore Ruthenate, Solid-State Reaction

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