Many Body Effects on Optical Properties of Graphene
13 Oct 2016 | Online Presentations | Contributor(s): Subhasis Ghosh
Graphene, a two-dimensional (2D) material shows remarkable optical and electronic properties, such as a linear energy dispersion, chirality and half-integer quantum Hall effect. Multilayer graphene flakes, held together by weak van der Waals forces have also attracted attention due to...
Heat Under the Microscope:
Uncovering the Microscopic Processes that Govern
04 Oct 2016 | Online Presentations | Contributor(s): Austin Minnich
n this talk, I will describe our efforts to uncover the microscopic processes that govern thermal transport by phonons. In particular, I will describe how our advances in computation and experiment have enabled the first direct measurements of thermal phonon transmission coefficients at solid...
Characterization of 2D materials at Birck Surface Analysis Facility
28 Sep 2016 | Online Presentations | Contributor(s): Dmitry Zemlyanov
Material characterization is an important aspect for various applications. In particularly, for 2D materials and nano-materials, the surface characterization becomes crucial for smart material design, functionalization, fabrication, etc. Surface Analysis Facility at Birck Nanotechnology Center,...
High Accuracy Atomic Force Microscope with Self-Optimizing Scan Control
19 Sep 2016 | Online Presentations | Contributor(s): Ryan (Young-kook) Yoo
Atomic force microscope (AFM) is a very useful instrument in characterizing nanoscale features, However, the original AFM design, based on piezo-tube scanner, had slow response and non-orthogonal behavior, inadequate to address the metrology needs of industrial applications: accuracy,...
Introduction to the Quantum Design Systems in the Birck Spintronics Lab
17 Aug 2016 | Online Presentations | Contributor(s): Neil R Dilley
Presentation about the design and capabilities of the PPMS DynaCool Cryostat and the MPMS-3 SQUID Magnetometer.
Plasmonics and Metasurfaces for Extreme Manipulation of Light
08 Mar 2016 | Online Presentations | Contributor(s): Yongmin Liu
In this talk, I will present some of our work in the fascinating field of plasmonics and optical metasurfaces. First, I will discuss reconfigurable plasmonic lenses operating in microfluidic environment, which can dynamically diverge, collimate and focus surface plasmons . Second, I will...
Adventures with Oxide Interfaces: Electronics, Magnetism, Memory, Energy and Biology
25 Feb 2016 | Online Presentations | Contributor(s): T. Venky Venkatesan
In this talk I share a personal close up view of the evolution of this field and where I see it going. I will cover polar/non-polar oxide interface conductivity, defect induced magnetism, FE tunnel junctions and some recent work on bio-oxide interfaces.
New Frontiers in Terahertz Technology
13 May 2015 | Online Presentations | Contributor(s): Mona Jarrahi
In this talk, I will describe some of our recent results on developing fundamentally new terahertz electronic/optoelectronic components and imaging/spectrometry architectures to mitigate performance limitations of existing terahertz systems.
Addressing Societal-scale Challenges with Nanoscale Materials: Flexible, Impedance-sensing “Smart Bandages” Enable Early Detection of Pressure Wounds
20 Apr 2015 | Online Presentations | Contributor(s): Sarah Swisher
In this talk, I will introduce our work developing solution-processed materials for flexible electronics, with emphasis on how these materials will enable new applications. I will then focus on one example: our recent development of a “smart bandage” prototype for detecting and...
Spaser in Quantum Regime
12 Feb 2015 | Online Presentations | Contributor(s): Mark I Stockman
The spaser have been introduced theoretically and discovered experimentally. We briefly consider quantum theory and latest results on spaser as an ultrafast quantum generator and amplifier of nanoplasmonic fields, ultrabright nanolabel, and highly-efficient nanosensor. We present latest original...
Coupling of Electron Spin Dynamics and Nanomechanical Motion in Carbon Nanotubes
20 Nov 2014 | Online Presentations | Contributor(s): Mark Rudner
Due to their low masses and high stiffnesses, nanostructures made out of atomically-thin carbon- based materials such as graphene and carbon nanotubes (CNTs) feature high mechanical oscillation frequencies and large zero-point vibration amplitudes. These properties open many avenues for...
Impedance Spectroscopy Methods Applied to Thermoelectric Materials and Devices
19 Nov 2014 | Online Presentations | Contributor(s): Jorge García-Cañadas
Impedance spectroscopy is one of the most helpful techniques for the characterization of a wide range of devices (solar cells, supercapacitors, fuel cells, etc.). However, it is not extensively used in the thermoelectric field and most of existing work is mainly focused on determining the figure...
Insight into Time-Resolved Photoluminescence Measurements on Thin-film Solar Cells using Numerical Simulations
09 Oct 2014 | Online Presentations | Contributor(s): Ana Kanevce
Increased efficiency in thin-film solar cells requires higher degree of understanding of the recombination mechanisms, and separating the various types of recombination involved. Time resolved photoluminescence (TRPL) measurement is a contactless and quick measurement method, and therefore one...
Ongoing Transformation of Computational Nanophotonics
18 May 2014 | Online Presentations | Contributor(s): Alexander V. Kildishev
Computational nanophotonics is one of the central tools of the science of light and photonic device engineering. It plays a crucial role in enabling optical technologies ranging from bio-sensing to quantum information processing. Up to the present, a plethora of various methods and commercial...
Coherent Nonlinear Optics, Backward Waves and Negative Spatial Dispersion
16 May 2014 | Online Presentations | Contributor(s): Alexander K. Popov
Extraordinary frequency-converting nonlinear-optical propagation processes associated with backward electromagnetic and elastic waves are described. Particular realizations of negative spatial dispersion which enable such waves are investigated.
Active Nanophotonics: From Coherent Control of Quantum Emitters to Plasmonic Nanolasers
28 Apr 2014 | Online Presentations | Contributor(s): Ken Shih
Light-matter interaction at nanometer scale is emerging as one of the most exciting fields in nanoscience. In combination with the advanced materials synthesis technique to tailor novel low-dimensional electronic systems, new doors are open toward design and realization of nanophotonic devices...
11 Apr 2014 | Online Presentations | Contributor(s): Hui Cao
Most of the research in the field of photonics has focused on understanding and mitigating the effects of disorder which are often detrimental. For certain applications, however, intentionally introducing disorder can actually improve the device performance, e.g., in photovoltaics optical...
Optical Multi-Dimensional Coherent Spectroscopy of Semiconductor Nanostructures
08 Apr 2014 | Online Presentations | Contributor(s): Steven Cundiff
I will give an introduction to optical two-dimensional coherent spectroscopy and then present our use of it to study optical resonances in semiconductor nanostructures. In quantum wells, our results show that many-body effects dominate the light-matter interaction for excitons in semiconductors...
Engineered Defects in Wide Band-gap Semiconductors for Single-spin Sensing and Computation
26 Mar 2014 | Online Presentations | Contributor(s): Abram Falk
Using infrared light at near-telecom wavelengths, I will show that spin states in silicon carbide exhibit long quantum coherence times that persist up to room temperature. I will also discuss new strategies for generating coherent spin interactions at the nanoscale using defects in inequivalent...
The Elusive Spin Transistor
11 Apr 2011 | Online Presentations | Contributor(s): Supriyo Datta
This presentation is a short introductory tutorial on spin-transistors.
Control of Spin Precession in a Datta-Das Transistor Structure
11 Apr 2011 | Online Presentations | Contributor(s): Hyun Cheol Koo
Transistors Switch onto Spin Using the spin of an electron in addition to, or instead of, the charge properties is believed to have many benefits in terms of speed, power-cost, and integration density over conventional electronic circuits. At the heart of the field of spintronics has been a...
Electric and Magnetic Properties of Multiferroic Oxide Thin Films and Heterostructures
20 Oct 2010 | Online Presentations | Contributor(s): Pedro Antonio Prieto
Outline:IntroductionPreparation methods for oxide thin filmsOxide thin films and heterostructures Multiferroic materialsBiFeO3, YMnO3, BiMnO3 thin films and FE/FM CompositesConclusions
TiCN/TiNbCN Multilayer System with Enhanced Tribological Properties
20 Oct 2010 | Online Presentations | Contributor(s): Pedro Antonio Prieto
Improvement in the mechanical properties of hard coatings such monolayer (TiN, CrN, AlCN, WC-Co, TiCN) , has been achieved using compositional gradient WC/C layer, or multilayered type [transition metal/transition carbide]n, [transition metal/transition nitride]n, [TiCN/ZrCN]n, among others....
Nanotechnology Activities in Colombia: A Perspective From the Excellence Center for Novel Materials
11 Oct 2010 | Online Presentations | Contributor(s): Pedro Antonio Prieto
I will present the current state of R & D in the fields of condensed matter, novel materials, and nanotechnology in Colombia. I will initially consider Latin America and the Caribbean (LAC) to then visualize individual developments, as well as those for the region as a whole in these fields of...
Transformative Power Semiconductor Technologies to Impact 21st Century Energy Economy, and Space and Defense Electronics
22 Sep 2010 | Online Presentations | Contributor(s): Krishna Shenai
This talk will focus on advanced power semiconductor materials, devices, circuits and systems that are needed in order to address this daunting challenge. Specifically we will discuss emerging silicon and wide bandgap materials and power devices, heterogeneous chip-scale power integration,...
Ripples and Warping of Graphene: A Theoretical Study
08 Jun 2010 | Online Presentations | Contributor(s): Umesh V. Waghmare
We use first-principles density functional theory based analysis to understand formation of ripples in graphene and related 2-D materials. For an infinite graphene, we show that ripples are linked with a low energy branch of phonons that exhibits quadratic dispersion at long wave-lengths. Many...
Surface Characterization Studies of Carbon Materials: SS-DNA, SWCNT, Graphene, HOPG
16 Feb 2010 | Online Presentations | Contributor(s): Dmitry Zemlyanov
In this presentation examples of surface characterization studies of carbon specimens will be presented. (1) In particularly, the systematic XPS (X-ray photoelectron spectroscopy) characterization of graphene grown on the SiC surface will be reported. This work demonstrates a use for XPS to...
X-ray Diffraction and Reflectivity Analysis of Thin Films and Nanomaterials
29 Dec 2009 | Online Presentations | Contributor(s): Mauro Sardela
A review of x-ray analysis techniques applied to the characterization of nanomaterials will be presented with focus on x-ray lab source instrumentation similar to the facilities available at the Birck Nanotechnology Center. Practical aspects of data acquisition and interpretation using x-ray...
04 Jun 2008 | Online Presentations | Contributor(s): Ian Appelbaum
"Electronics" uses our ability to control electrons with electric fields via interaction with their fundamental charge. Because we can manipulate the electric fields within semiconductors, they are the basis for microelectronics, and silicon (Si) is the most widely-used semiconductor for...
Linear and Nonlinear Optical Devices Based on Slow Light Propagation: Figures of Merit
19 May 2008 | Online Presentations | Contributor(s): Jacob B. Khurgin
Performance of optical delay lines and nonlinear devices based on slow wave propagation in photonic crystal waveguides in the presence of higher order dispersion is analyzed and compared with other slow light schemes, such as coupled resonators, media with electromagnetically-induced...
"Ab Initio" Theory of Novel Micro and Nanolasers
19 May 2008 | Online Presentations | Contributor(s): A. Douglas Stone
While the laser is one of the most important inventions of the past century and one of the most interesting and controllable non-linear systems in physics, there is surprisingly little predictive theory of lasing properties. Predicting lasing thresholds and output power far above threshold in...
Transmission of images with subwavelength resolution to distances of several wavelengths in microwave, terahertz and infrared ranges
08 Apr 2008 | Online Presentations | Contributor(s): Pavel Belov
The resolution of conventional imaging systems is restricted by thediffraction limit: the details smaller than half-wavelength of radiationcannot be resolved. Using novel engineered media with extreme opticalanisotropy and their waveguiding properties it is possible to overcomethe classical...
Plasmonic Metamaterials: Unusual Optics and Applications
28 Feb 2008 | Online Presentations | Contributor(s): Igor Smolyaninov
Surface plasmon-polaritons (or plasmons) are collective excitations of the conduction electrons and the electromagnetic field on the surface of such good metals as gold and silver. Near the frequency of surface plasmon resonance plasmons may perceive regular dielectrics as negative index...
Hexagonal Prism Blue Diode Laser Using Whispering Gallery Mode (WGM) Resonances
23 Oct 2007 | Online Presentations | Contributor(s): Sangho Kim
Semiconductor lasers have many important applications, including communication technologies, optical storage, printing, and molecular detection. The range of applications could be broadened significantly if the lasers could be made smaller and with lower threshold currents. Today’s in-plane...
Introduction of MEMS Activity at Nano/Micro System Engineering Lab., Kyoto University
15 Sep 2007 | Online Presentations | Contributor(s): Osamu Tabata
We are aiming at the realization of microsystems and nanosystems with novel and unique functions by integrating functional elements in different domains such as mechanics, electronics, chemistry, optics and biotechnology. These micro/nano systems are expected to be novel machines, which will...
On the Cross Roads of Biology and Nanotechnology – Selective DNA Nanopore Sensors
21 Mar 2007 | Online Presentations | Contributor(s): Samir Iqbal
The ability to manipulate and identify the properties of singlebiological molecules with the potential of characterizing biologicalprocesses at the most fundamental levels can significantly facilitaterapid diagnostics and therapeutics. Fabrication of solid-statedevices investigating bacteria,...
Nanotechnology: Considerations for Facility Design
21 May 2007 | Online Presentations | Contributor(s): John Weaver
The growing area of study broadly termed nanotechnology provides a new set of challenges to the facility designer. While evolutionary changes in the quality of clean spaces occur, it is the collaborative nature of this field that requires revolutionary changes in facility design. The main...
Electron Emission from Nanoscale Carbon Materials
15 May 2007 | Online Presentations | Contributor(s): Timothy S Fisher
Prior studies on electron emission show possibly beneficial effects ofnanoscale phenomena on energy-conversion characteristics. For example,recent work has shown that the electric field around a nanoscale fieldemission device can increase the average energy of emitted electrons. Weconsider here...
Finite Size Scaling and Quantum Criticality
09 May 2007 | Online Presentations | Contributor(s): Sabre Kais
The study of quantum phase transitions, which are driven by quantum fluctuations as a consequence of Heisenberg's uncertainty principle, continues to be of increasing interest in the fields of condensed matter and atomic and molecular physics. In this field we have established an analogy between...
Understanding Deformation Processes in Nanocrystalline Metals Through the Use of Real-time Electron Microscopy Techniques
03 May 2007 | Online Presentations | Contributor(s): Eric Stach
It is has long been known that the grain size of a material has a substantial effect on its mechanical strength, through the well-established Hall-Petch relationship. In the past decade or so, there has been a resurgence of interest in this topic resulting from the ability to create metals with...
Computer Simulation of Nanoparticles, Viruses, and Electrical Power-Generating Bacteria
20 Mar 2007 | Online Presentations | Contributor(s): Peter J. Ortoleva
Models of cells and nanometer-scale biosystems are presented that clarify their physico-chemical characteristics and allow for computer- aided design of therapeutic and nanotechnical devices. Multiscale techniques are used to obtain rigorous, coarse-grained equations for the migration and...
Introduction to X-ray Photoelectron Spectroscopy and XPS Application for Biologically Related Objects
14 Feb 2007 | Online Presentations | Contributor(s): Dmitry Zemlyanov
X-ray Photoelectron Spectroscopy (XPS), which is known as Electron Spectroscopy for Chemical Analysis (ESCA), is a powerful research tool for the study of the surface of solids. The technique becomes widely used for studies of the properties of atoms, molecules, solids, and surfaces. The main...
Dendrimer-Templated Catalyst for Controlled Growth of Single-Wall Carbon Nanotubes by Plasma-Enhanced CVD
20 Feb 2007 | Online Presentations | Contributor(s): Placidus Amama
Carbon nanotubes (CNTs) are an important class of materials with several technological applications because they possess unparalleled properties in terms of ballistic electrical conductivity, thermal conductivity, tensile strength, and sensitivity to chemical and biological agents. To exploit...
Highly Efficient Thermal Transport: The Application of Carbon Nanotube Array Interfaces
01 Feb 2007 | Online Presentations | Contributor(s): Baratunde A. Cola
Carbon nanotubes (CNTs) have received much attention in recent years for their extraordinary properties that through careful engineering may be leverage for the development of numerous advantageous applications. However, to date, only few CNT based applications exist in the market place. So when...