12-02 :: February/March 2012

nanotimes News in Brief

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A new laser fabrication technique developed at Harvard allows for the creation of precisely arranged silver nanoparticles that are disconnected in 3D and supported by a polymer matrix. The new technique may prove critical in the develop- ment of metamaterials. © Kevin Vora

it emits a burst of photons as bright as the surface of the sun in a flash lasting only 50 quadrillionths (5 × 10-14) of a second. Instead of shining through the material, that energy gets trapped within it, exciting the electrons within the material and achieving a phenomenon known as nonlinear absorption.

Inside the pocket where that energy is trapped, a chemical reaction can take place, permanently alte- ring the internal structure of the material. The pro- cess has previously been exploited for 2D and simple 3D metal nanofabrication.

“Normally, when people use femtosecond lasers in fabrication, they’re creating a wood pile structure: something stacked on something else, being sup- ported by something else,” explains Mazur.

Kevin Vora, SeungYeon Kang, Shobha Shukla, and Eric Mazur: Fabrication of disconnected three-dimensional silver nanostructures in a polymer matrix, In: Applied Physics Letters, Vol. 100(2012), Issue 6, February 06, 2012, Article 063120 [3 pages], DOI: 10.1063/1.3684277: http://dx.doi.org/10.1063/1.3684277