Self-organized nanostructures have been recently observed when femtosecond laser pulses were focused inside fused silica glass. We have shown that these nanostructures extend throughout the focal volume and their order is preserved over macroscopic distances when the focus is scanned. We discuss the present understanding of the formation of the nanostructures including a model based on transient nanoplasmonics. The model predicts the periodicity of nanoplanes to scale as λ/2 in the medium. This is experimentally verified at 800 nm and 400 nm light with which we obtain nanoplane spacing of 250 ± 20 nm and 140 ± 20 nm respectively, which scale as predicted. Another requirement of the model is that ionization occurs preferentially at regions that have previously been ionized. This allows an initially inhomogeneous plasma to develop into an ordered nanoplasma array. Using transmission measurements we show that the required "memory" exists in the case of fused silica.

Date Published: 3 October 2005
PDF: 10 pages
Proc. SPIE 5971, Photonic Applications in Nonlinear Optics, Nanophotonics, and Microwave Photonics, 59711D (3 October 2005); doi: 10.1117/12.629965

Published in SPIE Proceedings Vol. 5971:
Photonic Applications in Nonlinear Optics, Nanophotonics, and Microwave Photonics
Roberto A. Morandotti; Harry E. Ruda; Jianping Yao, Editor(s)