Fig. 3.

FWHM of the Hall crossover. The width was determined from the derivatives of the fits to R_H(B₂) in the crossed-field setup, to the simultaneously measured magnetoresistivity ρ(B₂), and to of the single-field experiment, respectively. See Fig. 1 Inset for the definition of the FWHM. The values for were scaled by 1/11 = B_2c/B_1c (ref. 13) to account for the c axis vs. ab plane magnetic anisotropy of YbRh₂Si₂. The solid line represents a linear fit to all datasets with the magnetoresistivity data being well described up to 1 K; see SI Text IV. Within the experimental accuracy this fit intersects the ordinate at the origin. Where there is overlap, our magnetoresistivity results are in good agreement with the FWHM directly extracted from the derivative of ρ(B₂) presented in ref. 20. The crossed-field data obtained earlier in a very limited temperature range (14) are in good agreement with both our results and the linear fit. The different temperature dependence found earlier was dominated by the former single-field results differing from ours. This difference is likely a result of an improved orientation procedure that became possible only in a substantially improved setup (see SI Text I). Arrow indicates the Néel temperature. Error bars are standard deviations.