Numerical calculation of the temperature evolution and profile of the field ion emitter in the pulsed-laser time-of-flight atom probe

Abstract

The temperature evolution and profile of metal field ion emitters under pulsed laser irradiation are solved numerically using an implicit alternating direction method. The temperature profile along the emitter axis at selected times and the temperature evolution curve at the emitter apex during and after the pulsed‐laser irradiation have been obtained. This numerical result shows that the emitter can cool down from the peak temperature by ∼20 K in less than 5 ns, and the heated region is very much localized to the irradiated part of the emitter. The cooling rate is higher for specimens of larger thermal diffusivity, and also if the laser pulse width is narrower and the laser heating is better localized. The peak temperature of the tip apex reached depends almost linearly on the incident flux of the laser beam.