Fig. 3
From: How to probe the spin contribution to momentum relaxation in topological insulators
The change in the low-temperature Hall effect under the influence of surface modification. a, b Black curves: the Hall voltage on pristine samples; a red curve: the Hall voltage after application of magnetic Cr7Zn; b blue curve: Hall voltage after the application of non-magnetic Ga7Zn. The temperature is 1.4 K. Dashed lines are linear fits to the low-field behaviour, from which the carrier densities are derived. The left-hand vertical axes indicate the absolute value of the Hall resistance measured; the right-hand axes indicate the Hall voltage normalised to its pristine value at 3 T, demonstrating that the relative change in Hall effect is the same for both surface modifications. Thus the change in carrier density is the same for both surface modifications, indicating that Cr7Zn and Ga7Zn offer equivalent electrostatic perturbations
