Open AccessHeating and rapid cooling of bulk glass after photoexcitation by a focused femtosecond laser pulse
Author(s) -
Masaaki Sakakura,
Masahide Terazima,
Yasuhiko Shimotsuma,
Kiyotaka Miura,
Kazuyuki Hirao
Publication year - 2007
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.15.016800
Subject(s) - materials science , femtosecond , thermal diffusivity , optics , borosilicate glass , laser , photoexcitation , diffusion , lens (geology) , dissipation , signal (programming language) , atomic physics , physics , programming language , computer science , composite material , thermodynamics , excited state , quantum mechanics
To investigate the energy dissipation process after focusing a femtosecond laser pulse inside a zinc borosilicate glass, the time-dependent lens effect in the laser focal region was observed by a transient lens (TrL) method. We found that the TrL signal after 100 ns can be explained clearly by thermal diffusion. By fitting the observed signal, we obtained the phase change due to temperature increase, the initial diameter of the heated volume and the thermal diffusivity. On the basis of the results, the temperature increase and the cooling rate were estimated to be about 1800 K and 1.7X10(8) Ks(-1), respectively. We have also observed the signal change on a 100 ns scale, which can not be explained by the thermal diffusion model. This change was attributed to the relaxation of the heated material.