Extended Data Fig. 8: Complete suppression of symmetry breaking QPI wave vectors at an intermediate temperature in CsV₃Sb_4.98Sn_0.02.

(a) dI/dV(r, V = −5 mV) map taken over a 40 nm square region of the Sb-terminated surface of CsV₃Sb_4.98Sn_0.02, and (b) associated Fourier transform (FT). Atomic Bragg peaks are enclosed in black circles, while the blue arrows point along the unidirectional electron scattering features. (c) FTs of dI/dV(r, V) maps taken at 15 K, 25 K and 36 K over the same region of the sample in (a, b). (d) Temperature-dependent FT linecuts along the red dashed lines in (b, c) normalized by subtracting the average FT ‘baseline’ away from any prominent peaks. We use 0.29 Å⁻¹ average transverse to and 0.04 Å⁻¹ average along the linecut direction to create curves shown in (d). (e) Amplitudes of the two sides of the q₂ wave vector (blue and red circles) corresponding to the peak heights denoted by red and blue arrows in (d). Error bars in (e) represent standard errors obtained by Lorentzian fits to data shown in (d). STM setup condition: (a–c) V_sample = −5 mV, V_exc = 1 mV, I_set = 50 pA.