Temperature dependent reflection electron diffraction study of In(111) and observation of laser-induced transient surface superheating

The high temperature behavior of the In(111) surface is investigated using reflection high-energy electron diffraction. The In(111) surface remains ordered when heated at a slow rate up to the highest temperature studied, 4 K below the bulk melting point, The surface vacancy density is observed to increase with temperature, however, the average random step terrace width remains unchanged from its value at room temperature. Transient surface superheating of the In(111) surface by 73 +/- 9 K above its bulk melting point is observed using 100-ps laser pulsed heating, which provides a heating rate of similar to10(12) Ks(-1). The dependence of the diffraction intensity on temperature gives a surface Debye temperature of 49 +/- 10 K, The possibility of surface annealing after laser superheating and melting is also investigated, but no annealing is observed. (C) 2001 Elsevier Science B.V. All rights reserved.