Effect of thermally induced surface defects on the optical anisotropy of Ag(110)

We show that the temperature dependence of the intensity of the similar to 1.7 eV peak in the reflection anisotropy spectrum of clean Ag(110) can be explained by considering the effect of thermally induced surface defects and the thermal shift in binding energy of the occupied surface state involved. Two simple models are used to quantify the defect formation energy and the length scale over which the contribution to the intensity of this reflection anisotropy spectroscopy (RAS) feature is quenched due to the presence of thermal defects. We have simulated the decrease in the RAS peak intensity with increased temperature, achieving consistency with related measurements on ion-bombarded and adsorbate-covered surfaces, and previous estimates of the defect activation barrier for the Ag(110) surface. This study demonstrates the potential of RAS as a tool for monitoring surface kinetic behavior.