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Bulk-type SSLB based on LLZ:Ta achieves high specific areal capacity and operational current densities.

Materials with a 5d 4 electronic configuration are generally considered to have a nonmagnetic ground state (J = 0). Interestingly, Sr2YIrO6 (Ir 5+ having 5d 4 electronic configuration) was recently reported to exhibit long-range magnetic order at low temperature and the distorted IrO6 octahedra were discussed to cause the magnetism in this material. Hence, a comparison of structurally distorted Sr2YIrO6 with cubic Ba2YIrO6 may shed light on the source of magnetism in such Ir 5+ materials with 5d 4 configuration. Besides, Ir 5+ materials having 5d 4 are also interesting in the context of recently predicted excitonic types of magnetism. Here we report a single-crystal-based analysis of the structural, magnetic, and thermodynamic properties of Ba2YIrO6. We observe that in Ba2YIrO6 for temperatures down to 0.4 K, long-range magnetic order is absent but at the same time correlated magnetic moments are present. We show that these moments are absent in fully relativistic ab initio band-structure calculations; hence, their origin is presently unclear.

The d-electron low temperature magnet NbFe2 is poised near the threshold of magnetism at ambient pressure, and can be tuned across the associated quantum critical point by adjusting the precise stoichiometry within the Nb1-yFe2+y homogeneity range. In a nearly critical single crystal (y= -0.01), we observe a T3/2 power-law dependence of the resistivity rho on temperature T and a logarithmic temperature dependence of the Sommerfeld coefficient gamma=C/T of the specific heat capacity C over nearly 2 orders of magnitude in temperature, extending down to 0.1 K.

Niagara is currently the fastest supercomputer accessible to academics in Canada. It was deployed at the beginning of 2018 and has been serving the research community ever since. This homogeneous 60,000-core cluster, owned by the University of Toronto and operated by SciNet, was intended to enable large parallel jobs and has a measured performance of 3.02 petaflops, debuting at #53 in the June 2018 TOP500 list. It was designed to optimize throughput of a range of scientific codes running at scale, energy efficiency, and network and storage performance and capacity. It replaced two systems that SciNet operated for over 8 years, the Tightly Coupled System (TCS) and the General Purpose Cluster (GPC) [13]. In this paper we describe the transition process from these two systems, the procurement and deployment processes, as well as the unique features that make Niagara a one-of-a-kind machine in Canada.

We present a systematic study of transport and thermodynamic properties of the Laves phase system Nb 1−y Fe 2+y . Our measurements confirm that Fe-rich samples, as well as those rich in Nb ͑for ͉y͉ Ն 0.02͒, show bulk ferromagnetism at low temperature. For stoichiometric NbFe 2 , on the other hand, magnetization, magnetic susceptibility, and magnetoresistance results point toward spin-density wave ͑SDW͒ order, possibly helical, with a small ordering wave vector Q ϳ 0.05 Å −1 . Our results suggest that on approaching the stoichiometric composition from the iron-rich side, ferromagnetism changes into long-wavelength SDW order. In this scenario, Q changes continuously from 0 to small, finite values at a Lifshitz point in the phase diagram, which is located near y = +0.02. Further reducing the Fe content suppresses the SDW transition temperature, which extrapolates to zero at y Ϸ −0.015. Around this Fe content magnetic fluctuations dominate the temperature dependence of the resistivity and of the heat capacity which deviate from their conventional Fermi-liquid forms, inferring the presence of a quantum critical point. Because the critical point is located between the SDW phase associated with stoichiometric NbFe 2 and the ferromagnetic order which reemerges for very Nb-rich NbFe 2 , the observed temperature dependences could be attributed both to proximity to SDW order or to ferromagnetism.

Combined application of (69,71)Ga NMR spectroscopy and quantum mechanical calculations reveals the chemical bonding in the digallides of Ca, Sr, and Ba. An analysis of the electron localization function (ELF) shows honeycomb-like 6(3) nets of the Ga atoms as the most prominent structural features in SrGa(2) and BaGa(2). For CaGa(2) a description of a 3+1-coordinated Ga atom is revealed by the ELF and by an analysis of interatomic distances. The NMR spectroscopic signal shift is mainly due to the Knight shift and is almost equal for the investigated digallides, whereas the anisotropy of the signal shift decreases with the radius of the alkaline-earth metals. Calculated and observed values of the electric field gradient (EFG) are in good agreement for CaGa(2) and BaGa(2) but differ by about 21 % for SrGa(2) indicating structural instability. Better agreement is achieved by considering a puckering of the Ga layers. For BaGa(2) an instability of the structure is indicated by a peak in the density of states at the Fermi level, which is shifted to lower energies when taking puckering of the Ga layers into account. Both structural modifications are confirmed by crystallographic information. The Fermi velocity of the electrons is strongly anisotropic and is largest in the (001) plane of the crystal structure. This results in an alignment of the crystallites with the [001] axis perpendicular to the magnetic field as observed in (69,71)Ga NMR spectroscopy and magnetic susceptibility experiments. The electron transport is predominantly mediated by the Ga-Ga p(x)- and p(y)-like electrons in the (001) plane. The specific heat capacity of BaGa(2) was determined and indicated the absence of phase transitions between 1.8 and 320 K.

The quinary members of the complex boride series Sc 2 FeRu 5−x Ir x B 2 were synthesized by arc melting the elements and characterized by powder and single-crystal X-ray diffraction as well as metallographic and energy-dispersive Xray analyses. The use of a 4d/5d mixture allows distinguishing these elements with X-ray diffraction methods, thus enabling the study of site preference and its influence on the magnetic properties. The magnetic measurements reveal several changes of magnetic ordering within the series: from antiferromagnetism (Sc 2 FeRu 5 B 2 ) to ferromagnetism (Sc 2 FeRuIr 4 B 2 ) and finally to metamagnetism (Sc 2 FeIr 5 B 2 ). Within the quinary series, the magnetic moments continuously increase with increasing amounts of Ir in one (8j) of two possible Wyckoff sites. The members with x = 2 and 3 represent the first hard magnetic borides of transition metals.