California NanoSystems Institute
CNSI
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December 01, 2009

Leo Radzihovsky
Physics
University of Colorado at Boulder
Ultra-cold and dilute condensed matter physics
A steady progress in cooling and trapping technology has enabled a realization of degenerate alkali atomic gases. In this setting of micro-Kelvin temperatures, despite their extreme diluteness, these trapped gases exhibit a rich behavior akin to that found in conventional condensed matter systems, albeit in very different regimes and probed with very different techniques. Starting with a demonstration of Bose-Einstein condensation in bosonic atoms and Fermi sea in fermionic ones, the fields has seen an explosion of activity and discoveries ranging from vortex lattices to resonant paired superfluidity. I will present an overview of the milestones in this burgeoning field, will discuss recent developments and speculate about future ones.

November 24, 2009

Keith Schwab
Applied Physics
California Institute of Technology


Streaming Video

Cooling a mechanical resonator close to the quantum ground state
The tools to prepare mechanical structures in fundamental quantum states are being rapidly developed, using both optical and electrical techniques. The first major goal of this community is to prepare and measure the quantum ground state. To accomplish this, we are preforming experiments with a mechanical resonator parametrically coupled to a electrical resonator. The mechanical resonator is a very low dissipation (Q>1M), 6 MHz, nanomechanical structure; the electrical resonator is a lithographic, low dissipation (Q=20,000), superconducting niobium, 7.5 GHz resonator. We pump this structure with carefully prepared microwave photons and demonstrate cooling of the mechanical structure of quantum occupation =3.8. The quantum ground state, <<1, appears within reach with a modified device.

November 17, 2009

Martin Keller
Biological and Environmental Sciences
Oak Ridge National Laboratory


Streaming Video

The BioEnergy Science Center: From Nano to Macro. An Integrated Strategy to Understand and Overcome Biomass Recalcitrance
The challenge of converting cellulosic biomass to sugars is the dominant obstacle to cost-effective production of biofuels. The BioEnergy Science Center (BESC), funded by the Department of Energy, will address this challenge with an unprecedented interdisciplinary effort focused on overcoming the recalcitrance of biomass. In addition to Oak Ridge National Laboratory (ORNL), the team consists of Dartmouth College, the University of Georgia, the Georgia Institute of Technology, the University of Tennessee, the National Renewable Energy Laboratory, the Samuel Roberts Noble Foundation, four industrial partners, and individual principal investigators from various institutes. By combining engineered plant cell walls to reduce recalcitrance with new biocatalysts to improve deconstruction, BESC will revolutionize the processing of biomass. These breakthroughs will be achieved with a systems biology approach integrating from nanotechnology to large scale experiments and new highthroughput analytical and computational technologies to achieve (1) targeted modification of plant cell walls to reduce their recalcitrance (using Populus and switchgrass as high-impact bioenergy feedstocks), thereby decreasing or eliminating the need for costly chemical pretreatment; and (2) consolidated bioprocessing, which involves the use of a single microorganism or microbial consortium to overcome biomass recalcitrance through single-step conversion of biomass to biofuels. This talk will provide an overview and update of ongoing research within BESC and will highlight significant breakthroughs in these areas.

November 10, 2009

G.P. Li
Calit2
University of California, Irvine


Streaming Video

LifeChips Research and Development at UC Irvine
Concurrent revolutions in biology, medicine, physical sciences and engineering at the micro and nano scale, accompanied by advances in instrumentation, are bringing these historically separate disciplines into convergence. This exciting trend has the potential to bring about dramatic and important changes to life science and micro/nanoelectronics technology: in the results of research, in the way that research is performed, and in the development of a new hybrid industry based on this convergence. LifeChips is the study of nature's 3 billion years of evolution (technology of life), and development of micro-and nano-scale technologies, systems and devices that combines methods developed by life scientists and technologists to help solve fundamental problems in the life sciences and in engineering (technology for life). LifeChips represents a new research paradigm that has driven the need for collaborations among researchers from traditionally different backgrounds and cultures, namely life scientists (biologists, medical researchers) and technologists (physical scientists, engineers). It also represents the fusion of two major industries, the microelectronic chip industry with the life science industry. UC Irvine is spearheading development in LifeChips on many fronts: initiating graduate training programs, developing design methodologies, defining new applications, promoting commercialization, creating research programs, and pursuing novel LifeChips manufacturing techniques. LifeChips research projects at UC Irvine provide excellent examples of potential new science discovery and engineering products, including implantable microdevices, minimally invasive devices, cell analysis chips, and biosensors. In addition to utilizing micro/nano chip technologies, each project and device has unique requirements for its design, manufacture and deployment. These requirements (and limitations) drive the need for advances in nano/micro fabrication and system-integration at manufacturing level, building the foundations for a new LifeChips industry. We will discuss several projects at UC Irvine to illustrate the flavor of LifeChips research.

October 27, 2009

Mervyn Miles
Physics
Bristol University


Streaming Video

High-speed AFM meets the Holographic Assembler
High-speed AFM is important for following processes occurring on short time scales inaccessible to conventional AFM. We are working on two versions: one is capable of extremely high imaging rates and can image over relatively large areas on samples with relatively large height variations, and the other is a noncontact version which is more appropriate for studying single molecular bio processes in liquid. Both are also capable of writing structure,s e.g., by electrochemical oxidation, at high-speed. The majority of our examples are biological. At the same time, we have been developing a holographic optical tweezers instrument capable of assembling, sometimes automatically, structures which go from individual nanotools to photonic bandgap crystals. The nanotools can be used, e.g., to manipulate living cells or can become an independent AFM probes operating with all degrees of freedom (see http://HoloAssembler.com). We are now interfacing to both of these instruments via a multitouch table which greatly increases their versatility and accessibility to the non-expert user.

October 20, 2009

Jeanie Lau
Physics & Astronomy
University of California, Riverside


Streaming Video

Electrons in the Flatland: Graphene Nanoelectronics
Graphene, a two - dimensional single atomic layer of carbon, is the ultimate realization of the "flatland". On the one hand, it is an extraordinary conductor and a promising candidate for electronic materials; on the other hand, it is also thinnest elastic membrane. In this talk I will present our results on both of these aspects: (1) novel transport phenomena in graphene, including coherent interference of multply-reflected charge waves, p-n-p junctions and gate-tunable supercurrent Josephson effect; and (2) ripple formation and manipulation on suspended graphene sheets. I will conclude the talk with a brief discussion on the fascinating prospect of strain-based graphene engineering.

October 13, 2009

Dennis Matthews
Department of Applied Science and School of Medicine
University of California, Davis


Streaming Video

Application of Photon-Based Science and Nano-Technology to Bioscience and Medicine
Biophotonics, the application of photon-based technologies and methods to bioscience and medicine, is becoming an increasingly important means of diagnosing and treating disease as well as studying the underlying mechanisms which govern how living organisms function. There is also now a large community of researchers around the globe who are actively creating and applying biophotonics tools and methods. Industry is also a major player in the field of biophotonics since it represents a $50B/yr global market sector and there is a constant need to develop, manufacture and distribute biomedical and scientific instrumentation. Despite these efforts there are many areas in bioscience and medicine that can benefit from a concerted and global interdisciplinary effort in both research and translation of biophotonics devices, software, fluorescent probes and methods. Some examples of the challenges include the development of portable and ruggedized point-of-care technologies for diagnosing and treating patients in remote areas or even metropolitan regions in the aftermath of a pandemic event. Non-invasive biophotonic devices are well suited to and would be especially valuable for these applications. New methods of imaging that do not rely on large instrumentation or ionizing radiation are needed for providing critical diagnoses for stroke and traumatic brain injury victims. Of course, there also needs for of early cancer diagnosis from analyzing blood samples and, of most importance, a means of treating metastatic disease through molecular-based targeting of cancer cells. Treatment of infections using photodynamic therapy can also be explored as a means to avoid use of antibiotics. Many other major challenges arise in bioscience and medicine including characterization and distillation of stem cells, identification and destruction of cancer stem cells, image guidance of ultra-precision surgery, to name but a few opportunities for the application of biophotonics tools and methods. In my presentation, I will review some highlights for the field of biophotonics and then talk about new opportunities for research as well as medical and scientific device development. I will also describe a new "Biophotonics for Life Consortium" we in the community are forming and how it can provide a coordinated global effort to meet some of the grand challenges that continue to exist in medicine and bioscience.
October 07, 2009

Timothy M. Swager
Chemistry
Massachusetts Institute of Technology


Streaming Video

Sensors Based on Conjugated Polymers and Carbon Nanotubes
Organic electronic materials display a diversity of function and performance unmatched by conventional electronic materials. Optimal implementation requires sophisticated molecular designs and complex syntheses, which are often lacking in sensory materials. I will discuss our efforts to create new generations of sensory materials that exhibit specific resistive changes to target analytes rather than emissive responses. The advantages of chemiresistive sensors include the following: (1) Small changes in resistance can be measured with high precision and inexpensive electronics. (2) Resistivity sensors have very low power requirements. (3) Resistive materials are readily integrated into many different structures, ranging from integrated circuits to fabrics. (4) The simplicity of a resistive measurement is ideal for the formation of cross-reactive array (e-nose or e-tongue) devices.

Restricted geometries created by nanostructures will be used to impart superior sensitivity to chemical sensors. The obvious advantage in these types of systems is increased interfacial area to interact with the analytes, however for chemiresistors these systems can realize much larger gains. Conducting polymer-carbon nanotubes (CNTs) composites can create sensory devices with finite numbers of conduction pathways. For single-walled CNTs (SWCNTs), analyte induced resistance changes occur along the length of the nanotube as well as at the junctions. An impressive illustration of the selectivity possible involves wrapping SWCNTs with a conducting polymer containing calix[4]arene receptors (Figure 1). SWCNTs are naturally p-doped generally responsive to chemicals with oxidizing/reducing/polar characteristics and these factors can yield selective responses. However, we have succeeded in generating selective CNT sensors with differential responses to non-polar o-, m-, and p-xyelene. We have further identified opportunities for creating sensors from multiwalled carbon nanotubes (MWCNTs) using modular covalent functionalization schemes. In this scheme, the outer most shell of the MWCNT functionalized heavily and the internal CNTs are responsible for the conduction.

Figure 3. Schematic illustration of a conducting polymer-CNT sensor that exhibits a differential response to xylenes (shown bottom right).