We report results of magnetization, specific heat, and muon spin relaxation (μSR) measurements on single crystals of disorder-free Yb 3+ triangular lattice Yb(BaBO 3 ) 3 . The magnetization experiments show anisotropic magnetic properties with Curie-Weiss temperatures θ ⊥ = −1.40 K (H ⊥ c) and θ = −1.16 K (H c) determined from low-temperature data. The absence of both long-range antiferromagnetic order and spin freezing is confirmed down to 0.27 K at zero field. A two-level Schottky anomaly due to the opening of the ground-state Kramers doublet is observed from the low-temperature specific heat measurements when the applied magnetic fields μ 0 H > 0.7 T. At zero field, the increase of both C mag /T and the muon spin relaxation rate λ below 1 K is due to the electronic spin excitations, which often exist in quantum magnets where dipole-dipole interactions create an anisotropy of magnetic properties. The spin excitation is also supported by the unusual maximum of the field dependence of λ due to the field-induced increase in the density of excitations. We argue that dipolar interaction is dominant and induces the spin dynamics in the quantum magnet Yb(BaBO 3 ) 3 .
We report the results of muon spin rotation and relaxation (μSR) measurements on the recently discovered layered Cu-based superconducting material La 2 (Cu 1−x Ni x ) 5 As 3 O 2 (x = 0.40 and 0.45). Transverse-field μSR experiments on both samples show that the temperature dependence of superfluid density is best described by a two-band model. The absolute values of zero-temperature magnetic penetration depth λ ab (0) were found to be 427(1.7) and 422(1.5) nm for x = 0.40 and 0.45, respectively. Both compounds are located between the unconventional and the standard BCS superconductors in the Uemura plot. No evidence of time-reversal symmetry breaking in the superconducting state is suggested by zero-field μSR measurements.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.