Diffuse-light-scattering study of Pb(110) surface-roughening-melting transition

It is shown that diffuse-light (DL) scattering is sensitive to the surface atomic roughening transition and the surface melting transition, both of which occur on the Pb(110) surface, and have been independently characterized using high-resolution low-energy diffraction and other techniques. From the DL scattering we also show that the long-range surface-step fluctuations are destroyed during the process of cooling after the surface is heated up above the surface melting temperature, revealing the irreversible nature of the transition. This irreversibility of the transition was not observed using techniques other than DL.