Magnetic structures of rare earth intermetallic compounds RCuAs (R = Pr, Nd, Tb, Dy, Ho, and Yb)
arXiv:1603.03704 · doi:10.1016/j.jpcs.2017.07.004
Abstract
Neutron scattering studies have been carried out on polycrystalline samples of a series of rare earth intermetallic compounds RCuAs (R = Pr, Nd, Dy, Tb, Ho and Yb) as a function of temperature to determine the magnetic structures and the order parameters. These compounds crystallize in the ZrCuSi type structure, which is similar to that of the RFeAsO (space group P4/nmm) class of iron-based superconductors. PrCuAs develops commensurate magnetic order with K = (0, 0, 0.5) below T = 6.4 (2) K, with the ordered moments pointing along the c-axis. The irreducible representation analysis shows either a or representation. NdCuAs and DyCuAs order below T = 3.54(5) K and T = 10.1(2) K, respectively, with the same ordering wave vector but the moments lying in the a-b plane (with a or representation). TbCuAs and HoCuAs exhibit incommensurate magnetic structures below T = 9.44(7) and 4.41(2) K, respectively. For TbCuAs, two separate magnetic ordering wave vectors are established as K = (0.240,0.155,0.48) and K = (0.205, 0.115, 0.28), whereas HoCuAs forms a single K = (0.121, 0.041, 0.376) magnetic structure with 3 order harmonic magnetic peaks. YbCuAs does not exhibit any magnetic Bragg peaks at 1.5 K, while susceptibility measurements indicate an antiferromagnetic-like transition at 4 K, suggesting that either the ordering is not long range in nature or the ordered moment is below the sensitivity limit of 0.2 .
arXiv comment8 figures
References in corpus (6)
- High-temperature superconductivity in iron-based materials
- Superconducting phases of f-electron compounds
- Slow crossover in YbXCu4 intermediate valence compounds
- Enhanced electrical resistivity before Néel order in the metals, RCuAs (R= Sm, Gd, Tb and Dy
- Magnetic and transport anomalies in the compounds, RCuAs2 (R= Pr, Nd, Sm, Gd, Tb, Dy, Ho, and Er)
- Magnetic, electrical resistivity, heat-capacity and thermopower anomalies in CeCuAs2