Table of Contents
Laser Chemistry
Volume 2010, Article ID 148268, 15 pages
http://dx.doi.org/10.1155/2010/148268
Review Article

Elastic and Thermal Dynamics in Femtosecond Laser-Induced Structural Change Inside Glasses Studied by the Transient Lens Method

1Kyoto University Office of Society-Academia Collaboration for Innovation, Kyoto 615-8520, Japan
2Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
3Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan

Received 13 September 2010; Accepted 25 November 2010

Academic Editor: Chunlei Guo

Copyright © 2010 Masaaki Sakakura et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A technique to study femtosecond laser induced structural change inside glasses, the transient lens (TrL) method, is described. Because the TrL method is sensitive to the refractive index change around the photoexcited region, the time dependence of the density, pressure, and temperature changes, which accompany refractive index change, can be monitored over a broad range of timescales. In the picosecond-nanosecond time range, the pressure wave generation was observed as an oscillating TrL signal. By comparing the TrL signal with that calculated based on thermoelastic simulation, the density, pressure, and temperature changes in the photoexcited region can be estimated. In the longer time range (nanoseconds—milliseconds), the thermal diffusion process was observed. By fitting the TrL signal with that simulated based on thermal diffusion, the temporal evolution of the temperature distribution was obtained. Based on these observations, the features of femtosecond laser-induced structural change inside glasses are revealed. The advantages of the TrL method are described.