A thermal-controlling mechanism for laser ablation of a colossal magnetoresistant oxide target

Both angle- and time-resolved quadrupole mass spectrometric and time-resolved optical emission spectrometric techniques were employed to investigate the laser ablation mechanism of a colossal magnetoresistant target. It is suggested that the ablation process is generally thermal in nature when the laser fluence is not very high (<2.5 J/cm2). This viewpoint is supported by many experimental observations, such as the independence of the kinetic energy of the ablated species on their mass, the ambient gas pressure effect on the kinetic energy of ablated species, the existence of a laser fluence threshold as well as the plume expansion in an ambient gas.