Gonçalo Almeida successfully defends MSc thesis

Gonçalo P. Almeida (second from the left), visiting researcher at L2I, successfully defended his MSc thesis titled ‘Optical signal characterisation in Laser-Induced Breakdown Spectroscopy’. Gonçalo was supervised by our GoLP colleague Prof. João M. Dias (left). The thesis panel also included L2I members Hugo Pires (second from the right) and Gonçalo Figueira (right).

In his work, he characterised the plasma optical emission under the influence of varying experimental conditions, by studying their effect on signal intensity and measurement variability. A dedicated test bench was assembled at L2I and the ultrashort Amphos laser system was used as the pulsed light source.

The main results showed that, for ultrashort pulse durations and fluences below 22±6 J/cm2, the signal intensity varies linearly with the pulse energy. The analysis also revealed the existence of two maxima, and a slight defocus was shown to improve plasma generation.

Concerning signal collection, an optimal magnification that maximizes the collected emission was found. Additionally, the impact of the chromatic focal shift was verified and the isotropic nature of the plasma emission was demonstrated.

Congratulations, Gonçalo!