Fig. 2
From: Nonlinear magnetotransport shaped by Fermi surface topology and convexity
Nonlinear magnetoresistance with a temperature-driven inversion in WTe2. a Angular-dependent second-harmonic resistance R2ω measured at T = 300 K for a 34 nm thick WTe2 device with the current applied at 45° from the a axis of WTe2 crystal. The solid line is a sinusoidal fit (−ΔR2ωsinφ) to the data. A vertical offset was subtracted for clarity. b, c Current I (b) and magnetic field H (c) dependence of the sinusoidal amplitude ΔR2ω at room temperature. The solid lines are linear fits to the data. d ΔR2ω extracted at different temperatures under H = 14 T and I = 1 mA. The insets illustrate the position of the Fermi level in different temperature ranges. ‘e’ and ‘h’ indicates the electron and hole pocket, respectively. e Field dependence of the Hall resistance Rxy at three representative temperatures (red lines are to guide the eye). f Experimental temperature dependence of the electron ne and hole nh densities (points, bottom and left axes), overlaid with the Fermi level dependence of ne and nh as calculated ab-initio (lines, top and right axes)
