Local and Reversible Change of the Reconstruction on Ge(001) Surface between c(4x2) and p(2x2) by Scanning Tunneling Microscopy

The reconstruction on Ge(001) surface is locally and reversibly changed between c(4x2) and p(2x2) by controlling the bias voltage of a scanning tunneling microscope (STM) at 80K. It is c(4x2) with the sample bias voltage V_b =< -0.7V. This structure can be kept with V_b =< 0.6V. When V_b is higher than 0.8V during the scanning, the structure changes to p(2x2). This structure is then maintained with V_b >= - 0.6V. The observed local change of the reconstruction with hysteresis is ascribed to inelastic scattering during the electron tunneling in the electric field under the STM-tip.