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Niv Levy, Tong Zhang, Jeonghoon Ha, Fred Sharifi, Alec Talin, Young Kuk, Joseph A. Stroscio
Topological superconductors (TS) are a newly predicted phase of matter which is topologically distinct from conventional superconducting condensates of Cooper pairs. As a manifestation of its topological character, TS supports massless itinerant quasi
Tong Zhang, Niv Levy, Jeonghoon Ha, Young Kuk, Joseph A. Stroscio
Electrical field control of the carrier density of topological insulators (TI) has greatly expanded the possible practical use of these materials. However, the combination of low temperature local probe studies and a gate tunable TI device remains
The surface-directed growth of nanowires (NWs) has been demonstrated for a number of semiconductors and is anticipated to be applicable to a wider group of materials. However, the epitaxial relationship between NWs and their underlying surface has not been
Aaron M. Katzenmeyer, Vladimir Aksyuk, Andrea Centrone
Photothermal Induced Resonance (PTIR) is a new technique which combines the chemical specificity of IR spectroscopy with the lateral resolution of Atomic Force Microscopy. PTIR requires a pulsed tunable laser for sample excitation and an AFM tip to measure
Photo Thermal Induced Resonance (PTIR), recently attracted great interest for enabling chemical identification and imaging with nanoscale resolution. In this work, electron beam nano-patterned polymer samples were fabricated directly on 3-dimentional zinc
Brian G. Bush, Frank W. DelRio, Cherno Jaye, Daniel A. Fischer, Robert F. Cook
The interfacial properties of n-alkylsilane self-assembled monolayers on silicon were investigated by normal force spectroscopy and lateral force measurements and correlated with molecular structure via near-edge X-ray absorption fine structure (NEXAFS)
Ravikiran Attota, Victor Vertanian, Steve Olson, Robert Edgeworth, Iqbal Ali, Craig Huffman, Pate Moschak, Harry Lazier, Elizabeth Lorenzini
The exceptional z-height resolution of TSOM, as well as very fast measurement time, is particularly important for high volume manufacturing. These two attributes make TSOM advantageous for 3D-stacked IC measurements of TSV reveal structures, and C4 bumps
Sherrie R. Elzey, De-Hao D. Tsai, Lee L. Yu, Michael R. Winchester, Michael E. Kelley, Vincent A. Hackley
We report the development of a hyphenated instrument with the capacity to quantitatively characterize aqueous suspended gold nanoparticles (AuNPs) based on a combination of gas-phase size separation, particle counting, and elemental analysis. A customized
Michael D. Anderson, Colby L. Heideman, Qiyin Lin, Mary Smeller, Robert S. Kokenyesi, Andrew Herzing, Ian M. Anderson, Douglas A. Keszler, Paul Zschack, David C. Johnson
Recently we reported that intergrowth compounds [(MSe)1+y]m(TSe2)n, with M = Pb, Bi Ce} and T = W, Nb, Ta} self assemble from designed precursors. The values of m and n represent, respectively, the number of MSe and TSe2 structural units of the unit cell
A key motivation for the original development of ultrasonic-AFM based methods was to enable measurements of elastic properties with nanoscale spatial resolution. In this chapter, we discuss the quantitative measurement of elastic modulus with ultrasonic
The purpose of this document is to provide guidance on the quantitative application of atomic force microscopy (AFM)to determine the size of nanoparticles2 deposited in dry form on flat substrates using height (z-displacement) measurement. Unlike electron
Electromagnetic waves in the microwave frequency range are an essential tool for the investigation of material and device properties across a broad range of applications. Examples of materials of interest include: ferroelectric materials, ferromagnetic
Constantine Y. Khripin, Xiaomin X. Tu, Jeffrey A. Fagan, Ming Zheng
Length fractionation of colloidal carbon nanotube dispersions is required for many studies. Size- exclusion chromatography (SEC) has been reported as a reliable method for high resolution length fractionation of DNA-dispersed single-wall carbon nanotubes
The principal objective of this work was to develop and demonstrate a new methodology for silver nanoparticle (AgNP) detection and characterization based on asymmetric-flow field flow fractionation (A4F) coupled to multiple detectors and using stable
Julien C. Gigault, Tae Joon Cho, Robert I. MacCuspie, Vincent A. Hackley
The application of asymmetrical-flow field flow fractionation (A4F) for gold nanorod (GNR) fractionation and characterization was comprehensively investigated. We report on two novel aspects of this application. The first addresses the analytical challenge
Aleksandr B. Stefaniak, Vincent A. Hackley, Gert Roebben, Kensei Ehara, Steve Hankin, Michael T. Postek, Iseult Lynch, Wei-En Fu, Thomas P. Linsinger, Andreas Th?nemann
There is a need to understand and manage potential risks posed to workers, the public, and the environment from exposure to engineered nanomaterials. In response, several organizations have developed lists of relevant nano-objects and of physico-chemical
Recently, the applications of transmission electron microscopy (TEM) related techniques have extended from ex situ nanoscale characterization of structure and chemistry of products to dynamic measurements of reaction processes. Commercially available
De-Hao D. Tsai, Frank W. DelRio, Sherrie R. Elzey, Suvajyoti S. Guha, Michael R. Zachariah, Vincent A. Hackley, Melanie P. Shelton
Dithiothreitol (DTT)-based displacement is widely utilized for separating ligands from their gold nanoparticle (AuNP) conjugates, a critical step for differentiating and quantifying surface-bound functional ligands and therefore the effective surface
Bartosz K. Nowakowski, Douglas T. Smith, Stuart Smith
This paper discusses the ongoing development of a vacuum-compatible, precision nano-indentation platform (PNP) that is directly traceable to Système International d'Unités (SI). In particular, results from recent initiatives to address environmental
Kristine A. Bertness, Norman A. Sanford, J. R. Montague, H.S. Park, Victor M. Bright, Charles T. Rogers
We have measured singly clamped cantilever mechanical-resonances in ensembles of as-grown gallium nitridenanowires (GaN NWs), from 12 K to 320 K. Resonance frequencies are approximately linearly dependent on temperature near 300 K with relative shifts of
Evaluation of aggregation and agglomeration of carbon nanotube (CNT) solution has been one of the key issues for applications. Here we introduce a simple method based on depolarized dynamic light scattering (DDLS) performed at multiple scattering angles to
Heayoung Yoon, Dmitry A. Ruzmetov, Paul M. Haney, Marina S. Leite, Behrang H. Hamadani, Albert A. Talin, Nikolai B. Zhitenev
We investigate local electronic properties of CdTe solar cells using electron beam to excite electron-hole pairs and evaluate spatially resolved photocurrent characteristics. Standard semiconductor processes were used to fabricate Ohmic metal contacts on
Zhao Z. Deng, Alexander Smolyanitsky, Qunyang Li, Xi-Qiao Feng, Rachel J. Cannara
We discuss a potential new measurement application based on nanotribological measurements and simulations of the model lamellar material graphite. While frictional forces always oppose motion, we have observed that friction increases with decreasing load
Craig D. McGray, Samuel M. Stavis, Joshua Giltinan, Eric Eastman, Samara L. Firebaugh, Jenelle Piepmeier, Jon C. Geist, Michael Gaitan
Super-resolution fluorescence microscopy is used for the first time to study the nanoscale kinematics of a MEMS device in motion across a surface. A device under test is labeled with fluorescent nanoparticles that form a microscale constellation of near
We have measured the characteristics of a high-speed (10 MHz) quadrant avalanche photodiode (APD) in order to detect high frequency resonant oscillations and tip displacements of a cantilever. Currently, no high-speed quadrant detectors with a response