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Search Publications by

Samuel M. Stavis (Fed)

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Displaying 1 - 25 of 55

Sub-picoliter Traceability of Microdroplet Gravimetry and Microscopy

December 20, 2021
Lindsay C. C. Elliott, Adam L. Pintar, Craig R. Copeland, Thomas B. Renegar, Ronald G. Dixson, B. Robert Ilic, R. Michael Verkouteren, Samuel M. Stavis
Volumetric analysis of single microdroplets is difficult to perform by ensemble gravimetry, whereas optical microscopy is often inaccurate beyond the resolution limit. To address the latter issue, we advance and integrate these complementary methods

Accurate localization microscopy by intrinsic aberration calibration

June 24, 2021
Craig Copeland, Craig McGray, Robert Ilic, Jon Geist, Samuel Stavis
A standard paradigm of localization microscopy involves extension from two to three dimensions by engineering information into emitter images, and approximation of errors resulting from the field dependence of optical aberrations. We invert this standard

Experimental Variation of Magnification Calibration for Localization Microscopy

September 15, 2019
Craig R. Copeland, Bojan R. Ilic, Samuel M. Stavis
We study the experimental variation of a localization microscope due to temporal and thermal factors, enabling elucidation of the discrepancy between transillumination brightfield and epi-illumination fluorescence of an aperture array for magnification

Bubble magnetometry of nanoparticle heterogeneity and interaction

June 7, 2019
Andrew L. Balk, Ian J. Gilbert, R. Ivkov, John Unguris, Samuel Stavis
Bubbles have a rich history as transducers in particle-physics experiments. In a solid-state analogue, we use bubble domains in nanomagnetic films to measure magnetic nanoparticles. This technique can determine the magnetic orientation of a single

Particle tracking of microelectromechanical system performance and reliability

October 25, 2018
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

Nanoparticle Manufacturing - Heterogeneity through Processes to Products

August 15, 2018
Samuel M. Stavis, Jeffrey Fagan, Michael Stopa, James Alexander Liddle
Commercial products are now making use of the unique properties of nanoscale particles. However, common challenges of making nanoparticles into products still limit their impact. In this article, we review recent advances in nanoparticle manufacturing in

Subnanometer localization accuracy in widefield optical microscopy

July 11, 2018
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

Aperture Arrays for Subnanometer Calibration of Optical Microscopes

September 28, 2017
Craig Copeland, Craig McGray, Jon Geist, James Alexander Liddle, Robert Ilic, Samuel Stavis
We fabricate and test subresolution aperture arrays as calibration devices for optical localization microscopy. An array pitch with a relative uncertainty of approximately three parts in ten thousand enables magnification calibration with subnanometer

Nanolithography Toolbox

October 19, 2016

Bojan R. Ilic, Krishna Coimbatore Balram, Daron A. Westly, Marcelo I. Davanco, Karen E. Grutter, Qing Li, Thomas Michels, Christopher H. Ray, Liya Yu, Neal A. Bertrand, Samuel M. Stavis, Vladimir A. Aksyuk, James A. Liddle, Brian A. Bryce, Nicolae Lobontiu, Yuxiang Liu, Meredith Metzler, Gerald Lopez, David Czaplewski, Leonidas Ocola, Pavel Neuzil, Vojtech Svatos, Slava Krylov, Christopher B. Wallin, Ian J. Gilbert, Kristen A. Dill, Richard J. Kasica, Kartik A. Srinivasan, Gregory Simelgor, Juraj Topolancik

The Nanolithography Toolbox

October 19, 2016
Krishna Coimbatore Balram, Daron Westly, Marcelo I. Davanco, Karen E. Grutter, Qing Li, Thomas Michels, Christopher H. Ray, Richard Kasica, Christopher B. Wallin, Ian J. Gilbert, Brian A. Bryce, Gregory Simelgor, Juraj Topolancik, Nicolae Lobontiu, Yuxiang Liu, Pavel Neuzil, Vojtech Svatos, Kristen A. Dill, Neal A. Bertrand, Meredith Metzler, Gerald Lopez, David Czaplewski, Leonidas Ocola, Kartik Srinivasan, Samuel Stavis, Vladimir Aksyuk, James Alexander Liddle, Slava Krylov, Robert Ilic
This article describes a platform-independent software package for scripted lithography pattern layout generation and complex processing. The Nanolithography Toolbox, developed at the Center for Nanoscale Science and Technology (CNST) at the National

Centroid and Orientation Precision of Localization Microscopy

March 11, 2016
Craig D. McGray, Craig R. Copeland, Samuel M. Stavis, Jon C. Geist
The concept of localization precision, which is essential to localization microscopy, is formally extended from optical point sources to microscopic rigid bodies. Measurement functions are presented to calculate the planar position, orientation, and motion

Optical Tracking of Nanoscale Particles in Microscale Environments

March 10, 2016
Pramod Mathai, James A. Liddle, Samuel M. Stavis
The trajectories of nanoscale particles through microscale environments record useful information about both the particles and the environments. Optical microscopes provide efficient access to this information through measurements of light in the far field

Quantitative magnetometry of ferromagnetic nanorods by microfluidic analytical magnetophoresis

September 3, 2015
Andrew L. Balk, Lamar O. Mair, Feng Guo, Carlos M. Hangarter, Pramod Mathai, Robert D. McMichael, Samuel M. Stavis, John Unguris
We introduce an implementation of magnetophoresis to measure the absolute magnetization of ferromagnetic nanorods dispersed in fluids, by analyzing the velocity of single nanorods under an applied magnetic field gradient. A microfluidic guideway prevents

Dimensional Reduction of Duplex DNA Under Nanofluidic Slit Confinement

August 19, 2015
Luis Fernando Vargas Lara, Jack F. Douglas, Samuel M. Stavis, Elizabeth A. Strychalski, Jon C. Geist, Brian J. Nablo
There has been much recent interest in the dimensional properties of duplex DNA under nanoscale confinement conditions as a problem of fundamental interest in both technological and biological fields. This has led to a series of measurements by

Characterization of Electrothermal Actuation with Nanometer and Microradian Precision

June 21, 2015
Craig R. Copeland, Craig D. McGray, Jon C. Geist, Vladimir A. Aksyuk, Samuel M. Stavis
A recently introduced particle-tracking method was used to measure the single motion cycles of an electrothermal actuator with nanometer and microradian precision. Driving the actuator with a low-noise input induced deterministic motion that was perfectly

Kilohertz Rotation of Nanorods Propelled by Ultrasound, Traced by Microvortex Advection of Nanoparticles

August 26, 2014
Andrew L. Balk, Lamar O. Mair, Pramod Mathai, Paul N. Patrone, Wei Wang, Suzanne Ahmed, Thomas Mallouk, James A. Liddle, Samuel M. Stavis
We measure the microvortical flows around gold nanorods propelled by ultrasound in water using polystyrene nanoparticles as optical tracers. We infer the rotational frequencies of such nanomotors assuming a hydrodynamic model of this interaction. In this