Fig. 1: Nc-AFM images of the S surface and Type-II surface in Co₃Sn₂S₂.

a Side view of the atomic model of the vertically stacked Sn-S-Co₃Sn-S-Sn layers in Co₃Sn₂S₂. b Schematic of the nc-AFM measurements using a qPlus sensor with a CO-functionalized tip. c STM image of the S surface of Co₃Sn₂S₂. d Chemical-bond-resolved nc-AFM image of the S surface taken in the blue square in (c). e Zoomed-in image from (d) to show the incomplete kagome pattern. Three distinct regions within a unit cell with bright, blurry, and dark contrast, which are marked by black solid line triangles, red solid line triangles, and a blue dashed line hexagon, are labeled as α_I, β_I, and γ_I regions. The atomic structure of S surface with the underlying Co₃Sn plane is superimposed. f STM image of the Type-II surface of Co₃Sn₂S₂. g Chemical-bond-resolved nc-AFM image of the Type-II surface taken in the area marked by a blue square in (f). h Zoomed-in image from (g), showing the kagome pattern. Three distinct regions within a unit cell with bright, blurry, and dark contrast, which are marked by black solid line triangles, red solid line triangles, and a blue dashed line hexagon, are labeled as α_II, β_II, and γ_II regions. The atomic structure superimposed is the Sn surface with the underlying S and Co₃Sn plane. Scanning parameters: c, f, V_s = −400 mV, I_t = 100 pA; d, e, amplitude = 100 pm, scanning height = 180 pm lower from a tunneling junction of V_s = −4 mV, I_t = 10 pA; g, h, amplitude = 100 pm, scanning height = 220 pm lower from a tunneling junction of V_s = −400 mV, I_t = 100 pA.