Impact of liquid environment on femtosecond laser ablation

The ablation rate by femtosecond laser processing of iron in different liquids is investigated for fluences up to 5 J/cm 2 . The resulting fluence dependency is modeled by an approach derived from the two-temperature model. In our experiments, the liquid environment strongly affects the effective penetration depth, e.g, the ablation rate in water is almost ten times higher than in toluene. This effect is discussed and introduced phenomenologically into the model. Additional reflectivity measurements and plasma imaging provide improved insight into the ablation process.