Abstract

We experimentally confirm the polarization dependent of multiphoton ionization and the polarization independent of avalanche ionization in the intensity regime of 10 TWcm^-2. By modeling the ultrafast laser interaction with bulk fused silica, we obtain the multiphoton ionization cross section for linear and circular polarization. Then we verify, both with experiments and numerical simulations, that circularly polarized picosecond pulses can be employed to improve the micromachining precision while keeping the machining efficiency.

© 2022 The Author(s)