skip to main content

Title: Identification of the formation phases of filamentary damage induced by nanosecond laser pulses in bulk fused silica

Employing a pump-probe polarization-based two-frame shadowgraphy setup, the formation of filamentary damage induced in bulk fused silica by a nanosecond pulse at 1064 nm is investigated with a picosecond probe. Three different phases are exhibited in the damage experiments. The first phase is the formation of a micrometric plasma channel along the laser direction during the beginning of the pulse likely caused by multi-photon ionization. This channel exhibits growth during ∼400 ps, and the newly grown plasma is discrete. Then, during the end of the pulse, this channel evolves into a tadpole-like morphology showing an elliptical head upstream the laser flux followed by a thin tail. This observed asymmetry is attributed to shielding effects caused by both the plasma and hot modified silica. Once the damage shows its almost final morphology, a last phase consists in the launch of a pressure wave enlarging it after the laser pulse. The physical mechanisms that might be involved in the formation of plasma channels are discussed. The experimental data are first confronted to the moving breakdown model which overestimates the filamentary damage length. Finally, taking into account the temporal shape of the laser pulses, the coupling between Kerr-induced self-focusing and stimulated Brillouin scattering ismore » discussed to interpret the observations.« less
Authors:
;  [1] ;  [2] ; ;  [1] ;  [3]
  1. College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)
  2. Aix Marseille University, CNRS, LP3 UMR 7341, Marseille 13288 (France)
  3. (China)
Publication Date:
OSTI Identifier:
22482063
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY; BREAKDOWN; BRILLOUIN EFFECT; DAMAGE; LASERS; MORPHOLOGY; MULTI-PHOTON PROCESSES; PLASMA; PULSES; SHAPE; SILICA