Fig. 6
a A series of STS spectra curves measured along the line starting from the core to the edge of the vortex, showing the peak of bound states splits into two at positions away from the vortex center. b The color image of a for a better view. The split peak positions in the STS spectra are marked by red crosses, and the dotted lines superimposed on the crosses indicate the start point of the peak splitting. c–g The experimental results for 2–6 QL samples, following the similar data process of (b). h A summary of the start points of the peak split, showing a crossover at 4 QL. a–h reprinted with permission from ref. 16, copyright 2015 by the American Physical Society)
