Observation of domain-wall dynamics in rare-gas monolayers at T=5 K

We have investigated the system Xe on graphite in the submonolayer coverage regime using scanning tunneling microscopy (STM) at T=5 K. The Xe adlayer forms hexagonal domains in a honeycomblike superstructure. Dynamic properties of the domain-walls could be studied for the first time by a series of STM images, revealing a time-dependent overlayer structure with the spontaneous creation and disappearance of the dislocations. In addition the influence of Xe island step edges on the local structure of the domain-walls of the Xe adlayer is discussed.