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Chemically Enhanced Carbon-Based Nanomaterials and Devices
09 Nov 2010 | | Contributor(s):: Mark Hersam
Carbon-based nanomaterials have attracted significant attention due to their potential to enable and/or improve applications such as transistors, transparent conductors, solar cells, batteries, and biosensors. This talk will delineate chemical strategies for enhancing the electronic and optical...
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MCW07 Exploring Trends in Conductance for Well-Defined Single Molecule Circuits
04 Apr 2009 | | Contributor(s):: Mark S Hybertsen
In our recent research, we have been able to measure and characterize the impact of intrinsic molecular properties on the conductance of single molecule circuits formed with amine-gold linkages. In this talk, I will review the experiments and the physical picture of the junction based on the...
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MCW07 A Quantum Open Systems Approach to Molecular-Scale Devices
25 Feb 2008 | | Contributor(s):: Yongqiang Xue
Experimental advances in electrically and optically probing individual molecules have provided new insights into the behavior of single quantum objects and their interaction with the nanoenvironments without requiring ensemble average. Molecular-scale devices are open quantum systems whose...
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MCW07 Physics of Contact Induced Current Asymmetry in Transport Through Molecules
25 Feb 2008 | | Contributor(s):: Bhaskaran Muralidharan, owen miller, Neeti Kapur, Avik Ghosh, Supriyo Datta
We first outline the qualitatively different physics involved in the charging-induced current asymmetries in molecular conductors operating in the strongly coupled (weakly interacting) self-consistent field (SCF) and the weakly coupled (strongly interacting) Coulomb Blockade (CB) regimes. The CB...
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Exploring Physical and Chemical control of molecular conductance: A computational study
31 Jan 2008 | | Contributor(s):: Barry D. Dunietz
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An Experimentalists’ Perspective
19 Dec 2007 | | Contributor(s):: Arunava Majumdar
This presentation was one of 13 presentations in the one-day forum, "Excellence in Computer Simulation," which brought together a broad set of experts to reflect on the future of computational science and engineering.
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MCW07 Modeling Molecule-Assisted Transport in Nanotransistors
06 Nov 2007 | | Contributor(s):: Kamil Walczak
Molecular electronics faces many problems in practical device implementation, due to difficulties with fabrication and gate-ability. In these devices, molecules act as the main conducting channel. One could imagine alternate device structures where molecules act as quantum dots rather than...
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MCW07 Impact of Porphyrin Functional Groups on InAs Gas Sensors
05 Nov 2007 | | Contributor(s):: Michael Garcia
Porphyrin molecules are often used for sensor engineering to improve sensitivity and selectivity to specific analytes. It is important to understand how the porphyrin HOMO-LUMO levels deplete surface states during functionalization of solid state sensors. Additionally, the effect of...
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Computing the Horribleness of Soft Condensed Matter
19 Oct 2007 | | Contributor(s):: Eric Jakobsson
A great triumph of computer simulations 40 years ago was to make the liquid state of matter understandable in terms of physical interactions between individual molecules. Prior to the first simulations of liquid argon and liquid water in the 1960's, there was no quantitatively rigorous molecular...
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Energy-level Alignment of Aryl Thiols Chemisorbed on Metal Surfaces: Implications for Molecular Electronic Junctions
27 Sep 2007 | | Contributor(s):: Roger D. van Zee
Charge-transport through the interface is a key part of the behavior of any electronic junction. One interface property important to molecular-electronic junctions is the energetic mismatch between the conductive levels of the molecule and the Fermi level of the contact material. This seminar...
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MCW07 Simple Models for Molecular Transport Junctions
13 Sep 2007 | | Contributor(s):: Misha Galperin, Abraham Nitzan, Mark Ratner
We review our recent research on role of interactions in molecular transport junctions. We consider simple models within nonequilibrium Green function approach (NEGF) in steady-state regime.
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MCW07 Conductance Switching in Fluorene/TiO2 Molecular Heterojunctions
13 Sep 2007 | | Contributor(s):: Richard L.McCreery
Molecular junctions consisting of a monolayer of fluorene and 10 nm of TiO2 between conducting contacts exhibit a memory effect upon positive polarization of the of the TiO2 for a few milliseconds. The junction conductance increases for a period of several minutes, but can be “erased” by a...
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MCW07 Molecular Electronics and the Bottom-up View of Electronic Conduction
12 Sep 2007 | | Contributor(s):: Supriyo Datta
Molecular electronics is commonly associated with the bottom-up approach to nanofabrication. My objective in this talk is to point out how it also leads to a bottom-up view of electronic conduction completely different from the standard top-down approach that starts from large conductors and...
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MCW07 Silicon Based Nanopore Sensors for Detection of DNA Molecules
11 Sep 2007 | | Contributor(s):: Samir Iqbal, Demir Akin, Rashid Bashir
Solid-state nanopores have emerged as possible candidates for next-generation DNA sequencing devices. In this talk, we will review our recent work in development of solid-state nanopore channels that are selective towards single strand DNA (ssDNA). Nanopores functionalized with a 'probe' of...
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MCW07 Electronic Level Alignment at Metal-Molecule Contacts with a GW Approach
05 Sep 2007 | | Contributor(s):: Jeffrey B. Neaton
Most recent theoretical studies of electron transport in single-molecule junctions rely on a Landauer approach, simplified to treat electron-electron interactions at a mean-field level within density functional theory (DFT). While this framework has proven relatively accurate for certain systems,...
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MCW07 Modeling Charging-based Switching in Molecular Transport Junctions
23 Aug 2007 | | Contributor(s):: Sina Yeganeh, Misha Galperin, Mark Ratner
We will discuss several proposed explanations for the switching and negative differential resistance behavior seen in some molecular junctions. It is shown that a proposed polaron model is successful in predicting both hysteresis and NDR behavior, and the model is elaborated with image charge...
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Amine Linked Single Molecule Circuits: Systematic Measurements & Understanding
02 Jul 2007 | | Contributor(s):: Mark S Hybertsen
Formation and function of well-defined linkages between organic molecules and metallic electrodes has been a key issue in the field of molecular electronics. We recently discovered that the conductance of single molecule junctions formed using gold-amine linkages can be measured reliably and...
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Orbital Mediated Tunneling in a New Unimolecular Rectifier
25 May 2007 | | Contributor(s):: Robert Metzger, NCN at Northwestern University
In 1997 we showed that hexadecylquinolinium tricyanoquinodimethanide is a unimolecular rectifier, by scanning tunneling microscopy and also as a Langmuir-Blodgett (LB) monolayer, sandwiched between Al electrodes. We have now seen rectification in a new molecule: this rectification can be followed...
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BNC Annual Research Symposium: Nanoelectronics and Semiconductor Devices
23 Apr 2007 | | Contributor(s):: David Janes
This presentation is part of a collection of presentations describing the projects, people, and capabilities enhanced by research performed in the Birck Center, and a look at plans for the upcoming year.
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CMOS-Nano Hybrid Technology: a nanoFPGA-related study
04 Apr 2007 | | Contributor(s):: Wei Wang
Dr. Wei Wang received his PhD degree in 2002 from Concordia University, Montreal, QC, Canada, in Electrical and Computer Engineering. From 2002 to 2004, he was an assistant professor in the Department of Electrical and Computer Engineering, the University of Western Ontario, London, ON, Canada....