Fig. 4: Light polarization dependence of surface state spin texture near Γ.
From: Weyl spin-momentum locking in a chiral topological semimetal
a Spin cuts corresponding to Fig. 3a measured with linear s- and p- polarized light and circular polarized light C± of opposite helicity. The black lines show fits to the data and the error bars indicate the statistical error due to counting statistics. b Direction of the resulting in-plane (ϕin-plane) and out-of-plane (θout-of-plane) surface state polarization components for the two surface states labeled with (i) and (ii) from a. Note that the extracted direction of s-pol. is unreliable, since the surface state is suppressed due to photoemission selection rules and thus the variation of the polarization across the surface state is within the statistical uncertainty. The black dashed lines correspond to the expected surface state spin-polarization orthogonal to the Fermi surface contour of the arc, c.f., Fig. 1c.
