A newly-discovered superconducting material, potassium-chromium-arsenic (K2Cr3As3), is a remarkable example of 3D nature in 1D single crystals. The shape of a single crystal typically is indicative of the dimensionality of certain properties. Researchers grew relatively large single crystals of K2Cr3As3 and found that the crystals grow as long thin rods. The morphology of the rods suggests 1D superconducting behavior, meaning that the superconducting state should be sustained in a much larger magnetic field when applied along the length of the rod than when the field is applied along other directions. However, the measurements were similar along different directions, indicating instead a 3D nature. Potentially a close relative of the iron-based high-temperature superconductors, the data suggest that the material may have a variety of intriguing properties, which researchers have only just begun to explore.
Anisotropic Hc2, Thermodynamic and Transport Measurements, and Pressure Dependence of Tc in K2Cr3As3 Single Crystals