California NanoSystems Institute
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March 13, 2007

Julia Phillips
Physical, Chemical, and Nano Sciences Center
Sandia National Laboratories

A Tour of Nanoscience Research at Sandia National Laboratories
Sandia National Laboratories was performing research on nanoscale phenomena long before "nanotechnology" became a buzzword. Today, Sandia and Los Alamos National Laboratories are constructing the Center for Integrated Nanotechnologies (CINT)*. These Centers are user facilities that are already beginning to host scientists from diverse institutions across the country (and beyond) to collaboratively attack nanoscience problems. In this talk I will describe CINT and the motivation for our current nanoscience effort. I will give examples of some of our recent research, including the invention of tools for nanoscience investigations (e.g., various scanning probe microscopies), research at the nano-bio interface (e.g., using motor proteins to move material across a surface), nanophotonics and nanoelectronics (e.g., low-dimensional semiconductor systems), and nanostructured materials (e.g., controlling the properties of quantum dots). Finally, I will describe some of the ways in which our nanoscience research is having an impact on the missions of Sandia National Laboratories, such as Energy.

* CINT is one of five nanoscience research centers across the United States funded by the DOE Office of Basic Energy Sciences.

March 06, 2007

Marc Hillmyer Associate Professor, Department Chemistry
University of Minnesota
Current Research

Streaming Video

Self-Assembly of Multicomponent Block Copolymers in Dilute Solution
Amphiphilic block copolymers self-assemble to give a variety of ordered structures when dispersed in water at low concentrations.

These aggregates can be used as drug delivery vehicles, rheology modifiers, artificial tissue scaffolds, and nanoreactors. The now well-established series of spherical micelles, wormlike micelles, and vesicles has been observed in dilute aqueous solution with various block copolymers that contain a water compatible block. Related structures have also been observed in other non-aqueous solvents using block copolymers containing at least one lyophilic segment.

Expanding the functionality and structural diversity of such self- assembling systems has been an important and emerging area of research. In this talk I will describe the synthesis and dilute solution self-assembly of (i) peptide-functionalized amphiphilic block copolymers, (ii) highly incompatible amphiphilic diblock copolymers containing fluorinated segments, and (iii) ABC miktoarm star terpolymers that contain one water soluble block and two hydrophobic and incompatible blocks joined at a common juncture.

Emphasis in this presentation will be on the modular synthetic approaches to these novel amphiphilic materials, characterization of their morphologies by cryogenic transmission electron microscopy, and specific molecular structure - micelle morphology relationships.

February 27, 2007

Michelle Simmons
School of Physics, University of New South Wales
Federation Fellow
Atomic Fabrication Facility
Program Manager
Atomic Fabrication and Crystal Growth

Streaming Video

Nano to Atomic-Scale Device Fabrication in Silicon
The driving force behind the microelectronics industry is the ability to pack ever more features onto a silicon chip, by continually miniaturising the individual components. However, after 2015 there is no known technological route to reduce device sizes below 10nm. In this talk we demonstrate a complete fabrication strategy towards atomic-scale device fabrication in silicon using phosphorus as a dopant in combination with scanning probe lithography and high purity crystal growth. Using this process we have fabricated conducting nanoscale wires with widths down to ~8nm, tunnel junctions, single electron transistors and arrays of quantum dots in silicon. We will present an overview of the devices that have been made with this technology and highlight some of the challenges to achieving atomically precise devices.

February 20, 2007

C. Patrick Collier
Assistant Professor, Chemistry & Chemical Engineering

California Institute of Technology

Current Research

Streaming Video

Biochemical Reaction Dynamics in Nanoscale Environments
The kinetic behavior of signaling pathways and other biochemical reaction networks have traditionally been characterized within the framework of the Michaelis-Menten formulism, which is derived from chemical kinetics based on the laws of mass-action appropriate for dilute, homogeneous solutions. However, evidence has indicated a breakdown of classical mass-action kinetics for reactions under dimensionally-restricted, confined or crowded conditions, such as those that occur in the in vivo nanoenvironments found inside a cell or cellular compartment. We have fabricated femtoliter-scale biomimetic compartments in microfluidics-based devices for capturing real-time single-molecule enzyme dynamics in confined and crowded spaces. We have found that fluctuation-dominated kinetic behaviors in single-enzyme reactions become increasingly important as the degree of confinement and crowding increase. This suggests that in addition to fluctuating enzyme conformation, stochastic fluctuations in local reactant concentrations in strongly diffusion-limited environments are responsible for the complex behavior seen in single-molecule enzyme kinetics

February 13, 2007

Duncan Stewart
Hewlett Packard Laboratories

Streaming Video

Physical and Electronic Structure of Nanoscale Molecular Monolayer Junctions
Organic monolayer coatings of inorganic surfaces offer the opportunity to fully engineer the physical, chemical and electronic structure of surfaces at the nanoscale, with broad applications in controlling chemical activity, solubility, friction, and more recently, electronic behavior. We report the physical and electronic characterization of metal / molecular monolayer / metal junction devices, built to deliver new nanoelectronic crossbar circuit functions. Particular emphasis is placed on combining quantitative chemical, physical and electronic characterization in a single test structure. To this end, we discuss physical characterization of the metal-organic interactions, including an in-vacuum delamination technique to access XPS and IR spectroscopy of the organic monolayers and the buried inorganic/organic interfaces. We correlate observed electrical switching behavior to this measured chemical and physical structure. In a quest to fabricate the best possible surfaces, we also describe detailed characterization of ultra-flat template-stripped Au and Pt metal electrodes and their dramatic impact on organic monolayer structure.

i) Blackstock et al., J. Phys. Chem. C 2007, 111, 16.
ii) Stewart et al., Nano Lett. 2004, 4, 133.
iii) Chen, Y. et al., Nanotechnology 2003, 14, 462.

February 06, 2007

Jinwoo Cheon
Department of Chemistry
Yonsei University

Streaming Video

Convergence Inorganic Nanocrystals
Inorganic nanocrystals are of current interest due to their novel properties and potential applications in nano-electronics and bio-medical technology. As a strategy for architectural control toward next generation multi-dimensional nanostructures, in specific, we demonstrate the convergence of various magnetic/optical/metallic nanocrystals and systematically elucidate the key growth parameters. Upon imposing the versatilities of these nanocrystals needed for cooperative biological functions, these convergence nanocrystals are capable of multi-modal diagnostics with ultra-sensitivity and selectivity for targeted bio-molecules. For example, based on in vitro cell studies and in vivo animal tests, our newly fabricated magnetic nanocrystals can provide 10 times more sensitive MRI detection capability than that of conventional materials. Our convergence nanocrystals can be further extended to other biomedical applications such as detection of pathogens and gene therapy.

1. Cheon et al. "Magnetic Superlattices and Their Nanoscale Phase Transition Effects" Proc. Natl. Acad. Sci. USA 2006, 103, 3023.
2. Jun et al. "Nanoscale Size Effect of Nanocrystals and Their Utilization for Cancer Diagnosis via Magnetic Resonance Imaging" J. Am. Chem. Soc. 2005, 127, 5732.
3. Lee et al. "Artificially Engineered Magnetic Nanocrystals for Ultra-Sensitive Molecular Imaging" Nature Medicine. 2006, in press.

January 30, 2007

Vincent Rotello
Professor of Chemistry
University of Massachusetts
Current Research

Streaming Video

Nanoparticles: Scaffolds and Building Blocks
Monolayer-protected nanoparticles provide versatile tools for nanotechnology. In our research, we use these nanoparticles as building blocks for the creation of functional magnetic and electronic nanocomposite materials. Simultaneously, we are using these particles as scaffolds for biomolecular recognition. These materials exploit the size (similar to that of proteins) and surface tunability of nanoparticles for applications including biomacromolecule recognition and delivery.

January 23, 2007

Kathryn Moler
Professor, Department of Applied Physics & Physics
Director, Center for Probing the Nanoscale, an NSF NSEC
Stanford University
Current Research

Streaming Video

Nanomagnetic Imaging

Scientists and engineers working to realize the potential of nanotechnology have at least one thing in common: we all need better tools for probing the nanoscale. In this talk, I will review the tools available for nanomagnetic imaging and manipulation, discussing both the general limiting factors and the most promising tools. I will conclude by analyzing the specific examples of magnetic force microscopy, scanning Hall probe microscopy, and scanning SQUID microscopy.
January 09, 2007

Carolyn Bertozzi
Professor of Chemistry
University of California, Berkeley
Current Research

Engineering Biological/Nanomaterial Interfaces
One of the most exciting applications of nanoscale science and technology is in the exploration of biological systems. This presentation will focus on recent work in our lab toward interfacing nanomaterials with living cells. Applications include cell patterning for microchip-based biosensors and carbon nanotube-based cell nanoinjectors.