Magnetic order in Nd${}_2$PdSi${}_3$ investigated using neutron scattering and muon spin relaxation

Abstract

The rare-earth based ternary intermetallic compounds $R_{2}T{X}_3$ ($R$ = rare-earth, $T$ = transition-metal, $X$ = Si, Ge, Ga, In) have attracted considerable interest due to a wide range of interesting low temperature properties. Here we investigate the magnetic state of Nd${}_2$PdSi${}_3$ using neutron diffraction, muon spin relaxation ($\mu$SR) and inelastic neutron scattering (INS). This compound appears anomalous among the $R_2$PdSi${}_3$ series, since it was proposed to order ferromagnetically, whereas others in this series are antiferromagnets. Although some members of the $R_{2}T{X}_3$ series have been reported to form ordered superstructures, our data are well described by Nd${}_2$PdSi${}_3$ adopting the AlB${}_2$-type structure with a single Nd site, and we do not find evidence for superlattice peaks in neutron diffraction. Our results confirm the onset of long range magnetic order below $T_0=17$~K, where the whole sample enters the ordered state. Neutron diffraction measurements establish the presence of a ferromagnetic component in this compound, as well as an antiferromagnetic one which has a propagation vector ${\mathbf{k}}_2=(1/2,1/2,1/4-\delta )$ with a temperature dependent $\delta \approx 0.02-0.04$, and moments orientated exclusively along the $c$-axis. $\mu$SR measurements suggest that these components coexist on a microscopic level, and therefore the magnetic structure of Nd${}_2$PdSi${}_3$ is predominantly ferromagnetic, with a sinusoidally modulated antiferromagnetic contribution which reaches a maximum amplitude at 11~K, and becomes smaller upon further decreasing the temperature. INS results show the presence of crystalline-electric field (CEF) excitations above $T_0$, and from our analysis we propose a CEF level scheme.

arXiv comment9 pages, 6 figures

References in corpus (10)

• Magnetic anisotropy, first-order-like metamagnetic transitions and large negative magnetoresistance in the single crystal of Gd${}_2$PdSi${}_3$
• Emergence of superconductivity in the canonical heavy-electron metal YbRh2Si2
• Observation of a temperature dependent electrical resistance minimum above the magnetic ordering temperature in Gd${}_2$PdSi${}_3$
• Large Low Temperature Magnetoresistance and Magnetic Anomalies in Tb${}_2$PdSi${}_3$ and Dy${}_2$PdSi${}_3$
• Magnetic, thermal, and transport properties on single crystals of antiferromagnetic Kondo-lattice Ce2PdSi3
• Magnetic behaviour of Eu_2CuSi_3: Large negative magnetoresistance above Curie temperature
• An unusual interplay among disorder, Kondo-effect and spin-glass behavior in the Kondo lattices, Ce${}_2$Au${}_{1-x}$Co${}_x$Si${}_3$
• Positive and negative pressure effects on the magnetic ordering and the Kondo effect in the compound Ce2RhSi3
• 4f-hybridization effect on the magnetism of Nd2PdSi3, an anomalous magnetic compound
• Superconducting behavior of the solid solution, Y2Pd(1-x)Pt(x)Ge3

Cited by in corpus (3)

• Magnetoelastic Coupling and Phases in the Skyrmion Lattice Magnet Gd2PdSi3 Discovered by High-resolution Dilatometry
• Magnetic and transport anomalies in R2RhSi3 (R= Gd, Tb, and Dy), resembling those of an exotic magnetic skyrmion Gd2PdSi3
• Complex single-site magnetism and magnetotransport in single-crystalline Gd${}_2$AlSi${}_3$