<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kevin Vora</style></author><author><style face="normal" font="default" size="100%">SeungYeon Kang</style></author><author><style face="normal" font="default" size="100%">Shobha Shukla</style></author><author><style face="normal" font="default" size="100%">Eric Mazur</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fabrication of disconnected three-dimensional silver nanostructures in a polymer matrix</style></title><secondary-title><style face="normal" font="default" size="100%">Applied Physics Letters</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://link.aip.org/link/?APL/100/063120/1</style></url></web-urls></urls><number><style face="normal" font="default" size="100%">6</style></number><publisher><style face="normal" font="default" size="100%">AIP</style></publisher><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">063120</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;n/a&lt;/p&gt;
</style></abstract><notes><style face="normal" font="default" size="100%">&lt;p&gt;n/a&lt;/p&gt;
</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kevin Vora</style></author><author><style face="normal" font="default" size="100%">SeungYeon Kang</style></author><author><style face="normal" font="default" size="100%">Eric Mazur</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A Method to Fabricate Disconnected Silver Nanostructures in 3D</style></title><secondary-title><style face="normal" font="default" size="100%">J Vis Exp</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012/11/27/</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.jove.com/details.stp?id=4399</style></url></web-urls></urls><publisher><style face="normal" font="default" size="100%">JoVE</style></publisher><pages><style face="normal" font="default" size="100%">e4399</style></pages><isbn><style face="normal" font="default" size="100%">1940-087X</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The standard nanofabrication toolkit includes  techniques primarily aimed at creating 2D patterns in dielectric media. Creating  metal patterns on a submicron scale requires a combination of nanofabrication  tools and several material processing steps. For example, steps to create planar  metal structures using ultraviolet photolithography and electron-beam  lithography can include sample exposure, sample development, metal deposition,  and metal liftoff. To create 3D metal structures, the sequence is repeated  multiple times. The complexity and difficulty of stacking and aligning multiple  layers limits practical implementations of 3D metal structuring using standard  nanofabrication tools. Femtosecond-laser  direct-writing has emerged as a pre-eminent technique for 3D nanofabrication.1,2 Femtosecond  lasers are frequently used to create 3D patterns in polymers and glasses.3-7 However, 3D metal direct-writing remains a challenge. Here, we describe a  method to fabricate silver nanostructures embedded inside a polymer matrix using  a femtosecond laser centered at 800 nm.  The method enables the fabrication of patterns  not feasible using other techniques, such as 3D arrays of disconnected silver  voxels.8 Disconnected 3D metal  patterns are useful for metamaterials where unit cells are not in contact with  each other,9 such as coupled metal dot10,11or coupled metal rod12,13 resonators. Potential applications include negative index  metamaterials, invisibility cloaks, and perfect lenses.In femtosecond-laser direct-writing, the laser  wavelength is chosen such that photons are not linearly absorbed in the target  medium. When the laser pulse duration is compressed to the femtosecond time  scale and the radiation is tightly focused inside the target, the extremely  high intensity induces nonlinear absorption. Multiple photons are absorbed  simultaneously to cause electronic transitions that lead to material modification  within the focused region. Using this approach, one can form structures in the  bulk of a material rather than on its surface.&lt;br /&gt;
Most work on 3D direct metal writing has focused  on creating self-supported metal structures.14-16 The method described here yields sub-micrometer silver structures that do not  need to be self-supported because they are embedded inside a matrix. A doped  polymer matrix is prepared using a mixture of silver nitrate (AgNO3),  polyvinylpyrrolidone (PVP) and water (H2O). Samples are then  patterned by irradiation with an 11-MHz femtosecond laser producing 50-fs pulses. During irradiation, photoreduction  of silver ions is induced through nonlinear absorption, creating an aggregate  of silver nanoparticles in the focal region. Using this approach we create silver  patterns embedded in a doped PVP matrix. Adding 3D translation of the sample  extends the patterning to three dimensions.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">69</style></issue><notes><style face="normal" font="default" size="100%">n/a</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>10</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kevin Vora</style></author><author><style face="normal" font="default" size="100%">SeungYeon Kang</style></author><author><style face="normal" font="default" size="100%">Shobha Shukla</style></author><author><style face="normal" font="default" size="100%">Eric Mazur</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Three-dimensional silver nanostructure fabrication through multiphoton photoreduction</style></title><secondary-title><style face="normal" font="default" size="100%">SPIE Proceedings Vol. 8247</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://spie.org/x648.html?product_id=906839</style></url></web-urls></urls><publisher><style face="normal" font="default" size="100%">SPIE</style></publisher><pub-location><style face="normal" font="default" size="100%">San Francisco, CA</style></pub-location><language><style face="normal" font="default" size="100%">eng</style></language></record></records></xml>