Fig. 3: Nematic superconductivity in 4Hb-TaS2.
a Critical fields of the flake sample at various temperatures. The critical field has a pronounced two-fold symmetry, whose anisotropy is larger at temperatures closer to the critical temperature. The current is applied at ϕ = 210°. b Similar measurement on a single crystal sample at T = 2.1 K, in which the crystal axes can be easily identified. The minimal critical field is observed when the field is applied parallel to the crystal’s a-axis. The current is applied at ϕ = 20°. Inset: micrograph of the single crystal sample with contacts attached. c Resistance measurements as a function of the applied magnetic field direction in the basal plane of the single crystal sample, for a constant magnetic field, ∣H∣ = 3.1 T, at T = 2.1 K. A peak in the resistance corresponds to a minimum in Hc2 at these angles. The various colors represent four different current directions, whose directions are specified in the legend. Clearly, the overall behavior is independent of the current direction. The two 120° data sets correspond to current leads put on two parallel faces of the crystal.
