Localized reversible nanoscale phase separation in Pr_0.63Ca_0.37MnO_3 single crystal using a scanning tunneling microscope tip

摘要

We report the destabilization of the charge ordered insulating (COI) state ina localized region of Pr_0.63Ca_0.37MnO_3 single crystal by current injectionusing a scanning tunneling microscope tip. This leads to controlled phaseseparation and formation of localized metallic nanoislands in the COI matrixwhich have been detected by local tunneling conductance mapping. The metallicregions thus created persist even after reducing the injected current to lowervalues. The original conductance state can be restored by injecting a currentof similar magnitude but of opposite polarity. We thus achieve reversiblenanoscale phase separation that gives rise to the possibility to "write, read,and erase" nanosized conducting regions in an insulating matrix with highspatial resolution.