Magnetic and superconducting properties of the Ir – rich compounds MIr<sub>3</sub> (M=Ce, Th and Nd)
ORAL
Abstract
Recently we have synthesized and studied CeIr3, NdIr3 and ThIr3 compounds that are members of the RE2m+nT4m+5n family (m, n > 0). The bulk nature of the superconducting transitions for CeIr3 and ThIr3 are evident from the visible anomalies at Tc = 2.5 K and 4.4 K, respectively. The heat capacity experiment revealed that CeIr3 is a weak-coupling BCS superconductor and ThIr3 is a moderately coupled type-II superconductor. Theoretical calculations indicate a multi-band character for the Fermi surfaces, with the dominating contribution to the density of states at the Fermi level coming from the 5d states of Ir.
In the case of NdIr3, our measurements indicate a ferromagnetic ground state with the Curie temperature TC = 10.6 K. The heat-capacity anomaly confirms the bulk nature of the transition, though Cp = 11.7 J mol−1K−1 is lower than expected for J = 9/2 and instead close to that of a J = 1/2 system. This suggests that the Nd ions are subject to a crystalline electrical field that removes spin degeneracy and leaves the Nd ions in a doublet ground state.
In the case of NdIr3, our measurements indicate a ferromagnetic ground state with the Curie temperature TC = 10.6 K. The heat-capacity anomaly confirms the bulk nature of the transition, though Cp = 11.7 J mol−1K−1 is lower than expected for J = 9/2 and instead close to that of a J = 1/2 system. This suggests that the Nd ions are subject to a crystalline electrical field that removes spin degeneracy and leaves the Nd ions in a doublet ground state.
*This work was supported by Ministry of Science and Higher Education (Poland) under project DI2016 020546. The work at Princeton was supported by the Department of Energy, Division of Basic Energy Sciences, Grant DE-FG02-98ER45706.
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Presenters
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Karolina Górnicka
- Faculty of Applied Physics and Mathematics, Gdansk University of Technology
- Gdansk University of Technology