Energy-partition Diagnostic for Measuring Time-resolved Scattering and Absorption in Burst-mode Laser Ablation

We describe an energy-partition diagnostic based on integrating sphere principle for measuring absorption and scattering in plasma-mediated ablation by a high repetition-rate (133 MHz), pulsetrain-burst ultrafast-pulse laser. The system time-resolves the partition of elastically scattered laser light into specular reflection, diffuse reflection, and transmission, giving access to per-pulse absorption dynamics. Physical events such as optical breakdown and incubation effects in glass and aluminum are illustrated.