Mark Hersam Seminar

Carbon nanomaterials have attracted significant attention due to their potential to improve applications such as transistors, transparent conductors, solar cells, batteries, and biosensors. In the seminar, Prof. Hersam highlight his latest efforts to develop strategies for purifying, functionalizing, and assembling carbon nanomaterials into functional devices. For example, he and his team has recently developed and commercialized a scalable technique for sorting surfactant-encapsulated single-walled carbon nanotubes (SWCNTs) by their physical and electronic structure using density gradient ultracentrifugation (DGU). The resulting monodisperse SWCNTs enhance the performance of thin film transistors, infrared optoelectronic devices, photovoltaics, catalysts, and transparent conductors. The DGU technique also enables multi-walled carbon nanotubes to be sorted by the number of walls and solution phase graphene to be sorted by thickness, thus expanding the suite of monodisperse carbon nanomaterials. By extending their DGU efforts to carbon nanotubes and graphene dispersed in biocompatible polymers (e.g., DNA, Pluronics, Tetronics, etc.), new opportunities have emerged for monodisperse carbon nanomaterials in biomedical applications. In addition to these solution-phase approaches, the seminar also discussed vacuum compatible methods for functionalizing the surfaces of carbon nanomaterials. For example, a suite of perylene-based molecules form highly ordered self-assembled monolayers (SAMs) on graphene via gas-phase deposition in ultra-high vacuum. Due to their noncovalent bonding, these SAMs preserve the superlative electronic properties of the underlying graphene while providing uniform and tailorable chemical functionality. In this manner, disparate materials (e.g., high-k gate dielectrics) can be seamlessly integrated with graphene, thus enabling the fabrication of capacitors, transistors, and related electronic/excitonic devices. Alternatively, via aryl diazaonium chemistry, functional polymers can be covalently grafted to graphene. In addition to presenting opportunities for graphene-based chemical and biological sensing, covalent grafting allows local tuning of the electronic properties of the underlying graphene.

Fermilab 2012

The operation of the Tevatron, the world’s second largest particle accelerator, at Fermilab was a coalition of efforts by numerous physics, material scientists, and engineers from diverse backgrounds ranging from particle physics, to polymer science and superconductivity. In our trip to the accelerator, measuring 1 kilometer in diameter, the AVS group had a chance visit many of the sites along its perimeter, while talking the primary actors involved in continuing the legacy left by the discovery of the bottom Omega baryon. Amongst the various sites seen, the group had an opportunity to tour within the DZero detector!

James Coleman Seminar

Semiconductor quantum dot lasers have been extensively studied for applications in future lightwave telecommunications systems. Prof. Coleman described the growth, processing and characteristics of quantum dot and nanostructure lasers that exhibit interesting and potentially important effects arising from reduction of the active medium to the quantum regime (<50 nm) in all three dimensions. The motivation for quantum dots in lasers was outlined along with methods for forming self-assembled and patterned quantum dots. The resultant laser characteristics was presented. Prof. Coleman introduced a novel inverted quantum dot structure or nanopore laser, containing three dimensional quantization formed from an engineered periodicity.

Vacuum Workshop 2012

Two-day vacuum workshop on April 17th and 18th 2012 from 11:00-1:00 pm in MRL 280!

Do you work with vacuum systems?
PLD? MBE? CVD? ALD? Sputtering?

Ever wonder how to build a vacuum chamber?
Ever wonder why your base pressure is too high?
Ever wonder what materials are vacuum compatible?
Ever wonder how to use a leak detector?

These are some of the questions we will be addressing at our two day vacuum workshop on April 17th and 18th from 11:00-1:00 pm in MRL 280!

The full list of topics are: gas and surface physics, vacuum technology, industry standards, component design and fabrication, system operation and safety.

Lunch will be provided.

To attend pre-register with the form at the bottom of this page. (Registration is now closed.)

Hosted by UIUC AVS Student Chapter. Presented by A&N Coorporation (http://www.ancorp.com/).

For more information, contact Frank Bergschneider at Fberg@ancorp.com or the UIUC AVS Student Chapter at illinoisavs@gmail.com

Engineering Open House 2012

At Engineering Open House, the AVS Student Chapter held exhibitions to introduce kids and adults to the fun of vacuum science. One exhibition involved the effects of atmospheric pressure on everyday objects, or more specifically: what would happen to peeps and shaving cream in space! Another bewildered even adults by freezing water after making it boil in a vacuum! Be sure to see our videos: peep in a vacuum, shaving cream in a vacuum, boiling water that freezes in a vacuum, balloon in vacuum, and candle in a vacuum!

Anthony Leggett Seminar

Quantum mechanics has been enormously successful in describing nature at the atomic level, and most physicists believe that it is in principle the "whole truth" about the world even at the everyday level. However, such a view primafacie leads to a severe problem: in certain circumstances, the most natural interpretation of the theory implies that no definite outcome of an experiment occurs until the act of "observation". For many decades this problem was regarded as "merely philosophical", in the sense that it was thought that it had no consequences which could be tested in experiment. However, in the last dozen or so years the situation has changed very dramatically in this respect. It is this problem that Prof. Leggett addressed by discussing some popular "resolutions”, the current experimental situation and prospects for the future.