Open AccessEvolution of polarization dependent microstructures induced by high repetition rate femtosecond laser irradiation in glass
Author(s) -
Fangteng Zhang,
Mindaugas Gecevičius,
Qiuqun Chen,
Hang Zhang,
Yong Dai,
Jianrong Qiu
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.021353
Subject(s) - irradiation , materials science , femtosecond , laser , optics , polarization (electrochemistry) , isotropy , microstructure , optoelectronics , physics , composite material , chemistry , nuclear physics
We report the observation of an anomalous polarization dependent process in an isotropic glass induced by long time stationary irradiation of a high repetition rate near-infrared femtosecond laser. Two distinctive types of polarization dependent microstructures were induced at different irradiation stages. At early stage (a few seconds), a dumbbell-shaped structure elongated perpendicularly to the laser polarization formed at the top of the modified region, which was later erased by further irradiation. At later stage (above 30 s), bubbles filled with O 2 formed by the irradiation, which were distributed along the laser polarization at a distance far beyond the radius of the laser beam. Based on a simple modeling of light reflection on boundaries, a thermal accumulation process was proposed to explain the formation and evolution of the dumbbell-shaped microstructure. The possible factors responsible for polarization dependent distribution of bubbles are discussed, which needs further systematic investigations. The results may be helpful in the development of femtosecond laser microprocessing for various applications.