Magnetic glassiness and crystal field effects on thermal and electrical properties of Er5Pd2-type compounds. (May 2022)

• Record Type: Journal Article
• Authors: Vaulin, A.A.; Chirkova, A.M.; Sherstobitova, E.A.; Shishkin, D.A.; Sherokalova, E.M.; Skokov, K.P.; Baranov, N.V.; Gubkin, A.F.
• Is Part Of: Intermetallics. Volume 144(2022)
• Publication Date: 2022-05
• Subjects: Crystal electric field -- Volumetric heat capacity -- Magnetocaloric effect -- Thermal expansion -- Electrical resistivity; Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2022.107519
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: Magnetic properties, thermal expansion, heat capacity, and electrical resistivity of the cluster-glass compound Er4.8 Pd2 and its paramagnetic isostructural counterpart Lu4.8 Pd2 have been studied in the temperature range 2–300 K and in applied magnetic fields up to 140 kOe. Short-range antiferromagnetic (AFM) correlations of localized magnetic moments of Er 3+ ions were found to develop in Er4.8 Pd2 on cooling below T * ≈ 40 K. A cluster-glass magnetic state was observed below freezing temperature T f ≈ 13.3 K, while Lu4.8 Pd2 showed paramagnetic behavior. The crystal electric field (CEF) was found to substantially affect both the heat capacity and the thermal expansion of Er4.8 Pd2 . The CEF splitting of the Er 3+ ion multiplet 4 I 15/2 was estimated to be as high as 280 K with a doublet ground state. Both the Schottky-type anomaly and short-range antiferromagnetic order contributions were found to give rise to a large volumetric heat capacity of Er4.8 Pd2 at low temperatures. High direct magnetocaloric effect with −Δ S M ( T )60 kOe = 18.8 J mole −1 K −1 was confirmed to exist in Er4.8 Pd2 while no inverse magnetocaloric effect was observed at low temperatures. Electrical resistivity of Er4.8 Pd2 revealed a non-metallic behavior at low temperatures which was ascribed to an inhomogeneous electronic state due to the formation of clusters with the AFM short-range correlations. Graphical abstract: Image 1 Highlights: Large volumetric heat capacity was observed in Er4.8 Pd2 at low temperatures. Crystal electric field effects on the thermal properties of Er4.8 Pd2 was estimated. Non-metallic electrical resistivity in Er4.8 Pd2 arises from glassy magnetic state. Large direct magnetocaloric effect was confirmed in Er4.8 Pd2 at low temperatures.