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Abstract The confluence between high-energy physics and condensed matter has produced groundbreaking results via unexpected connections between the two traditionally disparate areas. In this work, we elucidate additional connectivity between high-energy and condensed matter physics by examining the interplay between spin-orbit interactions and local symmetry-breaking magnetic order in the magnetotransport of thin-film magnetic semimetal FeRh. We show that the change in sign of the normalized longitudinal magnetoresistance observed as a function of increasing in-plane magnetic field results from changes in the Fermi surface morphology. We demonstrate that the geometric distortions in the Fermi surface morphology are more clearly understood via the presence of pseudogravitational fields in the low-energy theory. The pseudogravitational connection provides additional insights into the origins of a ubiquitous phenomenon observed in many common magnetic materials and points to an alternative methodology for understanding phenomena in locally-ordered materials with strong spin-orbit interactions.

Pseuodoscorpions (Pseudoscorpiones) have been little studied, although they are the third largest group in the Arachnida in number of species. Pseudoscorpions have features resembling those of true scorpions. Due to their small size (the largest pseudoscorpion being no larger than 1 cm) systematic studies have proven difficult. A high-performance microscope is necessary for detailed studies. In the present study, the pseudoscorpion Atemnus politus (Simon, 1878) collected in Osmaniye province, Turkey, was used to describe systematic and taxonomic characters, including chelicerae, pedipalps, walking legs, and cuticular structures on appendages using stereo light microscopy and scanning electron microscopy (SEM). The study revealed characteristic features of this species. This is the first SEM study of A. politus and provides an important contribution to understanding the morphology of pseudoscorpions and demonstrates the taxonomic value of SEM micrographs. Probable functions of some of the structures observed are discussed. [ABSTRACT FROM AUTHOR]

Strings of local excitations are interesting features of a strongly correlated topological quantum matter. Here, the authors show that Boltzmann-distributed strings of local excitations also describe the topological physics of the Santa Fe geometry of artificial spin ice, which is a classical thermal system.

The interplay between electronic transport and antiferromagnetic order has attracted a surge of interest as recent studies show that a moderate change in the spin orientation of a collinear antiferromagnet may have a significant effect on the electronic band structure. Among numerous electrical probes to read out such a magnetic order, unidirectional magnetoresistance (UMR), where the resistance changes under the reversal of the current direction, can provide rich insights into the transport properties of spin-orbit-coupled systems. However, UMR has never been observed in antiferromagnets before, given the absence of intrinsic spin-dependent scattering. Here, we report a UMR in the antiferromagnetic phase of a FeRh/Pt bilayer, which undergoes a sign change and then increases strongly with an increasing external magnetic field, in contrast to UMRs in ferromagnetic and nonmagnetic systems. We show that Rashba spin-orbit coupling alone cannot explain the sizable UMR in the antiferromagnetic bilayer and that field-induced spin canting distorts the Fermi contours to greatly enhance the UMR by 2 orders of magnitude. Our results can motivate the growing field of antiferromagnetic spintronics and suggest a route to the development of tunable antiferromagnet-based spintronics devices.

We investigate angular dependent spin-orbit torques from the spin Hall effect in a metallic antiferromagnet using the spin-torque ferromagnetic resonance technique. The large spin Hall effect exists in PtMn, a prototypical CuAu-I-type metallic antiferromagnet. By applying epitaxial growth, we previously reported an appreciable difference in spin-orbit torques for c- and a-axis orientated samples, implying anisotropic effects in magnetically ordered materials. In this work we demonstrate through bipolar-magnetic-field experiments a small but noticeable asymmetric behavior in the spin-transfer-torque that appears as a hysteresis effect. We also suggest that metallic antiferromagnets may be good candidates for the investigation of various unidirectional effects related to novel spin-orbitronics phenomena.