fig3

Figure 3. Enhanced spatial resolution by an O-decorated STM tip. (A) STM image of the Na₂IrO₃ surface taken with an O-decorated tip (V_b = -1.8 V,I_t = 20 pA, image size: 20 × 20 nm²). (B) Zoomed STM image from the region marked by black rectangle in (A). The superimposed Na, O and Ir atoms are represented with blue, red and pink balls, respectively. By measuring the line profiles, the distance between the nearest-neighboring Na atoms is 5.2 Å, and the length of Ir-O-Ir bonds is 3.1 Å. (C) Ultra-highly resolved image for the same area taken with V_b = -1.6 V.