No Thermal Roughening on Cu(110) up to 900 K

Abstract

We present energy-resolved He-scattering data on the thermal behavior of the clean Cu(110) surface. At variance with a recent x-ray study we have observed no evidence for a proliferation of steps, i.e., for thermal roughening, up to $T=900\mathrm{}$ K. The analysis points to an anomalous increase of the mean-square displacement of the surface atoms at temperatures $T\ge 550$ K which might be ascribed to an enhanced surface anharmonicity.