Crystal structure of the complex of 2,4,6-tri-ethyl-1,3,5-tris-[(4-methyl-1H-indazol-1-yl)meth-yl]-benzene with NH4PF6.

The complex of 2,4,6-tri-ethyl-1,3,5-tris-[(4-methyl-1H-indazol-1-yl)meth-yl]-benz-ene with ammonium hexa-fluorophosphate, C39H42N6·NH4 +·PF6 -, crystallizes in the monoclinic space group P21 with two mol-ecules of the receptor, two NH4 + and two PF6 - ions in the asymmetric unit. In each of the complexes the ammonium ion resides in the cavity of the receptor mol-ecule and is fixed in its position by three N-H⋯N bonds, while the remaining hydrogen atom of the cation acts as a bifurcated binding site for N-H⋯F bonding to the counter-anion. The crystal is composed of one-dimensional supra-molecular aggregates extending along the a-axis direction.

Magnon detection using a ferroic collinear multilayer spin valve.

Information transport and processing by pure magnonic spin currents in insulators is a promising alternative to conventional charge-current-driven spintronic devices. The absence of Joule heating and reduced spin wave damping in insulating ferromagnets have been suggested for implementing efficient logic devices. After the successful demonstration of a majority gate based on the superposition of spin waves, further components are required to perform complex logic operations. Here, we report on magnetization orientation-dependent spin current detection signals in collinear magnetic multilayers inspired by the functionality of a conventional spin valve. In Y3Fe5O12|CoO|Co, we find that the detection amplitude of spin currents emitted by ferromagnetic resonance spin pumping depends on the relative alignment of the Y3Fe5O12 and Co magnetization. This yields a spin valve-like behavior with an amplitude change of 120% in our systems. We demonstrate the reliability of the effect and identify its origin by both temperature-dependent and power-dependent measurements.

Complex Terahertz and Direct Current Inverse Spin Hall Effect in YIG/Cu1-xIrx Bilayers Across a Wide Concentration Range.

We measure the inverse spin Hall effect of Cu1-xIrx thin films on yttrium iron garnet over a wide range of Ir concentrations (0.05 ⩽ x ⩽ 0.7). Spin currents are triggered through the spin Seebeck effect, either by a continuous (dc) temperature gradient or by ultrafast optical heating of the metal layer. The spin Hall current is detected by electrical contacts or measurement of the emitted terahertz radiation. With both approaches, we reveal the same Ir concentration dependence that follows a novel complex, nonmonotonous behavior as compared to previous studies. For small Ir concentrations a signal minimum is observed, whereas a pronounced maximum appears near the equiatomic composition. We identify this behavior as originating from the interplay of different spin Hall mechanisms as well as a concentration-dependent variation of the integrated spin current density in Cu1-xIrx. The coinciding results obtained for dc and ultrafast stimuli provide further support that the spin Seebeck effect extends to terahertz frequencies, thus enabling a transfer of established spintronic measurement schemes into the terahertz regime. Our findings also show that the studied material allows for efficient spin-to-charge conversion even on ultrafast time scales.