Mechanism of laser assisted field evaporation from insulating oxides

M Tsukada; H Tamura; K P McKenna; A L Shluger; Y M Chen; T Ohkubo; K Hono

doi:10.1016/j.ultramic.2010.11.011

Mechanism of laser assisted field evaporation from insulating oxides

Ultramicroscopy. 2011 May;111(6):567-70. doi: 10.1016/j.ultramic.2010.11.011. Epub 2010 Dec 1.

Authors

M Tsukada¹, H Tamura, K P McKenna, A L Shluger, Y M Chen, T Ohkubo, K Hono

Affiliation

¹ WPI-AIMR, Tohoku University, 2-1-1 Katahira, Aobaku, Sendai, Japan. tsukada@wpi-aimr.tohoku.ac.jp

PMID: 21146934
DOI: 10.1016/j.ultramic.2010.11.011

Abstract

To explain the recent successful three-dimensional atom probe (3DAP) analyses of insulating oxides by laser assisted field evaporation, we investigated the mechanism of the laser-induced field evaporation of oxides by ab initio calculations. The calculated potential energy surfaces (PESs) for the ground and excited states indicated that the activation barrier height for field evaporation is substantially reduced by the accumulation of holes near the tip apex. This would make the direct electronic excitation possible to promote field evaporation along with thermal excitation. These theoretical calculations are supported by experimental observations.