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Abstract Low dimensional (LD) organic metal halide hybrids (OMHHs) have recently emerged as new generation functional materials with exceptional structural and property tunability. Despite the remarkable advances in the development of LD OMHHs, optical properties have been the major functionality extensively investigated for most of LD OMHHs developed to date, while other properties, such as magnetic and electronic properties, remain significantly under‐explored. Here, we report for the first time the characterization of the magnetic and electronic properties of a 1D OMHH, organic‐copper (II) chloride hybrid (C₈H₂₂N₂)Cu₂Cl₆. Owing to the antiferromagnetic coupling between Cu atoms through chloride bridges in 1D [Cu₂Cl₆²⁻]_∞chains, (C₈H₂₂N₂)Cu₂Cl₆is found to exhibit antiferromagnetic ordering with a Néel temperature of 24 K. The two‐terminal (2T) electrical measurement on a (C₈H₂₂N₂)Cu₂Cl₆single crystal reveals its insulating nature. This work shows the potential of LD OMHHs as a highly tunable quantum material platform for spintronics. 

Abstract Electrical generation and transduction of polarized electron spins in semiconductors (SCs) are of central interest in spintronics and quantum information science. While spin generation in SCs is frequently realized via electrical injection from a ferromagnet (FM), there are significant advantages in nonmagnetic pathways of creating spin polarization. One such pathway exploits the interplay of electron spin with chirality in electronic structures or real space. Here, utilizing chirality‐induced spin selectivity (CISS), the efficient creation of spin accumulation inn‐doped GaAs via electric current injection from a normal metal (Au) electrode through a self‐assembled monolayer (SAM) of chiral molecules (α‐helixl‐polyalanine, AHPA‐L), is demonstrated. The resulting spin polarization is detected as a Hanle effect in then‐GaAs, which is found to obey a distinct universal scaling with temperature and bias current consistent with chirality‐induced spin accumulation. The experiment constitutes a definitive observation of CISS in a fully nonmagnetic device structure and demonstration of its ability to generate spin accumulation in a conventional SC. The results thus place key constraints on the physical mechanism of CISS and present a new scheme for magnet‐free SC spintronics. 

We report a detailed study of the synthesis, composition, magnetic structure, and transport properties of a quasi-one-dimensional antiferromagnet FeBi4S7 that contains chains of edge-sharing FeS6 octahedra. High-resolution powder X-ray diffraction (PXRD) analysis, aided by variation of synthetic conditions, suggests that the true formula of the material is Fe1.2Bi3.8S7, due to the minor substitution of Fe into Bi sites. This finding is in agreement with crystal structure refinement from neutron powder diffraction data as well as with the small band gap of 0.23 eV determined from electrical transport measurements. Analysis of the neutron diffraction pattern collected below the antiferromagnetic ordering temperature of 64 K revealed ferromagnetic coupling between the Fe moments in the chains of FeS6 octahedra. The overall ordering, however, is antiferromagnetic due to the antiparallel arrangement of moments on neighboring chains. The collinear spin arrangement is described by a k-vector (1, 0, 1/2), which indicates doubling of the unit cell in the c direction and the loss of the C-centering translation as compared to the nuclear cell. The ferromagnetic nature of the sulfidebridged chains of Fe2+ ions in FeBi4S7, in contrast to the antiferromagnetic coupling between Fe moments in compounds with similar structural fragments, can be justified by the analysis of metric parameters that characterize the Fe−S bonding in these materials.