Compact Birefringent Waveplates Photo-Induced in Silica by Femtosecond Laser

Micromachines

Bertrand Poumellec¹  Matthieu Lancry¹  Rudy Desmarchelier¹  John Canning²  Kevin Cook² 

[1] Institut de Chimie Moléculaire et des Matériaux d'Orsay, UMR CNRS-UPSud 8182, Université de Paris Sud 11, Bâtiment 410, Orsay 91405, France;interdisciplinary Photonic Laboratories (iPL), School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia;

关键词: silica;    ultrafast processes in condensed matter;    laser-induced chemistry;    femtosecond phenomena;   

DOI  :  10.3390/mi5040825

来源: DOAJ

【 摘 要 】

Recently, we showed that femtosecond laser induced “nanogratings” consist of thin regions with a low refractive index (Δn = −0.15), due to the formation of nanoporous silica surrounded by regions with a positive index change. In this paper, we investigate a wide range of laser parameters to achieve very high retardance within a single layer; as much as 350 nm at λ = 546 nm but also to minimize the competing losses. We show that the total retardance depends on the number of layers present and can be accumulated in the direction of laser propagation to values higher than 1600 nm. This opens the door tousing these nanostructures as refined building blocks for novel optical elements based onstrong retardance.

【 授权许可】

Unknown