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Daniel S. Gruss, Chih-Chun Chien, Julio T. Barreiro, Massimiliano Di Ventra, Michael P. Zwolak
The density of states is a concept that is ubiquitous in classical and quantum physics, since it quantifies the energy distribution of states available in a system. Spectroscopic means allow its measurement over the entirety of a system's energy spectrum
Craig R. Copeland, Craig D. McGray, Jon C. Geist, Samuel M. Stavis
Microelectromechanical systems (MEMS) that require contact of moving parts to implement complex functions have demonstrated critical limits of performance and reliability. Here, we advance a particle tracking method to measure MEMS motion in operando at
One type of atomic force microscopy (AFM) used for critical dimension (CD) metrology is commonly referred to as critical dimension atomic force microscopy (CD-AFM); it uses flared tips and two-dimensional surface sensing to enable scanning of features with
Ndubuisi G. Orji, Mustafa Badaroglu, Bryan M. Barnes, Carlos Beitia, Benjamin D. Bunday, Umberto Celano, Regis J. Kline, Mark Neisser, Yaw S. Obeng, Andras Vladar
The semiconductor industry continues to produce ever smaller devices that are ever more complex in shape and contain ever more types of materials. The ultimate sizes and functionality of these new devices will be affected by fundamental and engineering
Hind El Hadri, Julien Gigault, Jiaojie Tan, Vincent A. Hackley
Applications of asymmetrical flow field-flow fractionation (AF4) continue to expand rapidly in the fields of nanotechnology and biotechnology. In particular, AF4 has proven valuable for the separation and analysis of particles, biomolecular species (e.g
Refractive index retrievals (also termed inverse Mie methods or optical closure) have seen considerable use as a method to extract the refractive index of aerosol particles from measured optical properties. Retrievals of an aerosol refractive index use two
Ronald G. Dixson, Ndubuisi G. Orji, Ichiko Misumi, Gaoliang Dai
Atomic force microscopes (AFMs) are commonly and broadly regarded as being capable of three dimensional imaging. However, conventional AFMs suffer from both significant functional constraints and imaging artifacts that render them less than fully three
Plasmomechanical systems - formed by introducing a mechanically compliant gap between metallic nanostructures - produce large optomechanical interactions that can be localized to deep subwavelength volumes. This unique ability opens a new path to study
Craig R. Copeland, Jon C. Geist, Craig D. McGray, Vladimir A. Aksyuk, James A. Liddle, Bojan R. Ilic, Samuel M. Stavis
The common assumption that precision is the limit of accuracy in localization microscopy and the typical absence of comprehensive calibration of optical microscopes lead to a widespread issue - overconfidence in measurement results with nanoscale
Rui Zhang, Robert Ilic, Yuxiang Liu, Vladimir Aksyuk
In this work, we design, fabricate and characterize monolithic, nanoscale Si3N4 tuning fork cavity optomechanical transducers with design enabled tuning of mechanical resonant frequencies and passive temperature compensation. Both frequency tuning and
Among the many classes of engineered nanomaterials, gold nanoparticles (GNPs) are one of the most widely studied and utilized nanoscale platforms for biomedical applications including diagnostics, therapeutics, and transfection. This is due in part to
This review article summarizes new scientific trends in research for metrology of small mass (1 milligram and lower) and small force (10 micronewtons and lower). After a brief introduction to the field, this paper provides an overview of recent
In subsurface imaging applications, contrast in EFM depends on the electrostatic force between the tip and sample. In the related technique, scanning Kelvin force microscopy (SKFM) contrast arises from the force due to capacitance gradient with tip-to
Ozgur B. Aslan, Isha M. Datye, Michal J. Mleczko, Karen Lau, Sergiy Krylyuk, Alina Bruma, Irina Kalish, Albert Davydov, Eric Pop, Tony F. Heinz
Ultrathin transition metal dichalcogenides (TMDCs) have recently been extensively investigated to understand their electronic and optical properties. Here we study ultrathin Mo0.91W0.09Te2, a semiconducting alloy of MoTe2, using Raman, photoluminescence
Contrast in electrostatic force microscopy (EFM) depends on the electrostatic force between the tip and sample. In the related technique, scanning Kelvin force microscopy (SKFM), contrast arises from the force due to the capacitance gradient with tip-to
Pin A. Lin, Bharath N. Natarajan, Michael P. Zwolak, Renu Sharma
During the catalytic synthesis of graphene, nanotubes, fibers, and other nanostructures, many intriguing phenomena occur, such as phase separation, precipitation, and processes similar to capillary action. The underlying mechanism of these processes and
Cedric J. Powell, Wolfgang Werner, Henryk Kalbe, Alexander Shard, David G. Castner
We assessed two approaches for determining shell thicknesses of core-shell nanoparticles (NPs) by X-ray photoelectron spectroscopy. These assessments were based on simulations of photoelectron peak intensities for Au-core/C-shell, C-core/Au-shell, Cu-core
Photothermal induced resonance (PTIR) is a scanning probe technique that provides sample composition information with a lateral resolution down to 20 nm. Interest in PTIR stems from its ability to identify unknown samples at the nanoscale thanks, in first
Cellulose nanocrystals (CNCs) are renewable, naturally derived polymeric nanomaterials that are receiving substantial attention for a wide range of potential applications. The recent availability of high quality reference materials will facilitate the