Observation of a phase transition from the phase to the phase induced by a STM tip

We have fabricated an (Formula presented)phase (Formula presented) crystal in the surface layer of a (Formula presented)phase (Formula presented) single crystal using a scanning tunneling microscope (STM) tip. After applying a relatively high bias voltage to the STM tip, we observed a significant change of the surface indicating the formation of the (Formula presented) phase near the exposed region. The STM image shows the characteristic triangular phase boundary between the original (Formula presented) phase (Formula presented) charge-density-wave superstructure) and the newly fabricated (Formula presented) phase (a triangular atomic lattice). Around the phase boundary, the local distortions of the (Formula presented) charge-density-wave superstructure have also been observed. The high-resolution STM image near the phase boundary suggests a sliding of the surface (Formula presented) atomic sheet by the STM modification procedure.