Structure-dependent lined up cone formations on pulsed laser ablated CdWO 4(010) single crystal: evidence of thermal quenching by surface defects for ablated particles

Abstract

Cones were formed with lined up in three different directions on CdWO 4(010) surface after pulsed laser ablation at 266 nm. One of the directions was along the μm-sized step structure on the surface. Electron probe microanalysis (EPMA) data showed many surface defects on the fresh surface. These structure-dependent lined up cone formations can be well analyzed on the basis of CdWO 4(010) surface structure in atomic scale. No cone formation was observed on a high purity and mechanically polished CdWO 4(010) single crystal with less surface defects. Time-of-flight mass spectroscopic data of the laser ablation on CdWO 4(010) with surface defects can be interpreted by the thermal quenching process responsible for cone formations on the surface.