Reversible 2D Phase Transition Driven By an Electric Field: Visualization and Control on the Atomic Scale

B. WORTMANN; D. VAN VÖRDEN; P. GRAF; R. ROBLES; P. N. ABUFAGER; N. LORENTE; C. A. BOBISCH; R. MÖLLER

NANO LETTERS (PRINT)

AMER CHEMICAL SOC

Lugar: Washington; Año: 2016 vol. 16 p. 528 - 533

1530-6984

ABSTRACT: We report on a reversible structural phasetransition of a two-dimensional system that can be locallyinduced by an external electric field. Two different structuralconfigurations may coexist within a CO monolayer onCu(111). The balance between the two phases can be shiftedby an external electric field, causing the domain boundaries tomove, increasing the area of the favored phase controllableboth in location and size. If the field is further enhanced newdomains nucleate. The arrangement of the CO molecules onthe Cu surface is observed in real time and real space atomic resolution while the electric field driving the phase transition is easily varied over a broad range. Together with the well known molecular manipulation of CO adlayers, our findings open exciting prospects for combining spontaneous long-range order with man-made CO structures such as ?molecule cascades? or ?molecular graphene?. Our new manipulation mode permitsus to bridge the gap between fundamental concepts and the fabrication of arbitrary atomic patterns in large scale, by providing unprecedented insight into the physics of structural phase transitions on the atomic scale.