Femtosecond laser-induced breakdown in water-like tissues: Influence of wavelength and pulse duration on electron dynamics

This study explores the initiation mechanisms of laser-induced breakdown in water-like tissues by examining the impact of ultra-short laser pulses at varying wavelengths. Using numerical simulations, we analyse the electron dynamics triggered by pulse durations from 1 fs to 150 fs at two specific wavelengths, 400 nm and 800 nm. The results highlight how shorter pulses predominantly drive photoionization due to their intense peak powers, while longer pulses facilitate cascade ionization, enhancing electron densities through prolonged interactions with the tissue. Our analysis reveals that the deeper penetration of 800 nm pulses allows for more significant cascade ionization effects, particularly at extended pulse durations, leading to a substantial increase in electron density. This study underscores the role of pulse duration and wavelength in influencing the primary ionization processes essential for laser induced breakdown, providing a foundation for optimizing laser applications in medical and material sciences.