Prof. Filler visits U. Chicago and U. South Florida

Prof. Filler recently gave invited talks at the James Franck Institute at the University of Chicago and at the Department of Chemical and Biomedical Engineering at the University of South Florida. In both cases, the title of his talk was "The Vapor-Liquid-Solid Mechanism: Encoding Heterogeneity at the Nanoscale" and featured the work of current student Dmitry Boyuk and former students Saujan Sivaram and Li-Wei Chou. 

 

Welcome Gözde Tütüncüoglu

We are excited to welcome Gözde Tütüncüoglu to the group as a postdoc. She received her Ph.D. from EPFL working with Anna Fontcuberta i Morral on the MBE growth of nanostructures. At Georgia Tech, Gözde will be working to understand and control thermal transport in semiconductor nanostructures. She is a joint member of the Filler and Maldovan groups. 

 
 

Prof. Filler gives invited talk at the MRS Fall Meeting in Boston, MA

Prof. Filler gave an invited talk in Symposium NM1 : Semiconducting Nanowires, Nanoribbons and Heterostructures—Synthesis, Characterizations and Functional Devices at the 2016 MRS Fall Meeting in Boston, MA. His talk, titled "Designing Next Generation Semiconductor Nanowire Growth Processes," showcased work from former students Naechul Shin and Saujan Sivaram as well as current student Ho Yee Hui. 

Saujan's paper featured on cover of Nano Letters

Saujan Sivaram's recently published paper “Surface Hydrogen Enables Subeutectic Vapor–Liquid–Solid Semiconductor Nanowire Growth” has been highlighted on the cover of the November 2016 issue of Nano Letters. Martin Ek created this stunning image.

The illustration shows the crucial role of surface chemistry in subeutectic vapor-liquid-solid nanowire synthesis. The nanowire (dark gray) in the background of the cover has hydrogen atoms (white balls) adsorbed on its sidewalls, allowing the AuGe catalyst (in gold) to remain in a supercooled liquid state. The loss of this surface passivation opens a pathway for catalyst atoms (gold balls) to access the nanowire sidewall, as shown by the nanowire in the foreground, which ultimately results in catalyst solidification.

Saujan's manuscript accepted to Nano Letters

Congratulations to Dr. Saujan Sivaram, the lead author on a manuscript titled "Surface Hydrogen Enables Sub-Eutectic Vapor-Liquid-Solid Semiconductor Nanowire Growth" that was recently accepted to the journal Nano Letters. Along with collaborators Ho Yee Hui, Dr. Maria de la Mata, and Prof. Jordi Arbiol, he showed that nanowire growth while the catalyst droplet is in a sub-cooled liquid state, a widely observed behavior, results from the presence of surface adsorbates that decorate the nanowire sidewall. These species act as a diffusion barrier, preventing the droplet from finding a low-barrier nucleation site. More generally, the ability of surface adsorbates to arbitrate the diffusion of species to/from the catalyst droplet opens new opportunities to choreograph nanowire growth, structure, and function.

Illustration of hydrogen desorption and subsequent catalyst droplet solidification. 

Illustration of hydrogen desorption and subsequent catalyst droplet solidification. 

Seeking postdoc applicants!

Martin Maldovan, Bara Cola, and I are in search of a postdoc to initiate a project to demonstrate a solid-state heat mirror. 

The ideal candidate would have experience with the vapor deposition (e.g., CVD or MBE) and physicochemical characterization (e.g., Raman, TEM, etc.) of multilayered crystalline materials. However, outstanding students with experience in related research areas (e.g., nanomaterials, thin films, surface science, heat transport fundamentals, etc.) will also be considered.

Interested? Please send your CV to me at: mfiller@gatech.edu