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Search Publications by: Jonathan E. Guyer ()

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Displaying 26 - 42 of 42

Kinetics Governing Phase Separation of Nanostructured Sn(x)Ge(1a 'x) Alloys.

June 5, 2006
Author(s)
Regina Regan, Harry A. Atwater, Jonathan E. Guyer, Erik Meserole, Mark S. Gorrsky
We have studied the dynamic phenomenon of SnxGe1a 'x/Ge phase separation during deposition by molecular beam epitaxy on Ge(001) substrates.Phase-separation leads to the formation of direct bandgap semiconductor nanowire arrays embedded in Ge oriented along

FiPy: A Finite Volume PDE Solver Using Python

September 1, 2005
Author(s)
Daniel Wheeler, Jonathan E. Guyer, James A. Warren
The solution of coupled sets of partial differential equations (PDEs) is ubiquitous in continuum models for phase transformations, such as in phase field or level et simulations. We are developing an object-oriented PDE solver, written in the Python

Phase-Field Modeling for Eutectic Solidification

April 1, 2004
Author(s)
Jonathan E. Guyer, William J. Boettinger, James A. Warren, Geoffrey B. McFadden
A diffuse interface (phase field) model for a simple electrochemical system is developed. We describe the minimal set of components needed to model an electrochemical interface and present a Lagrangian derivation of te governing equations. With a simple

Phase Field Modeling of Electrochemistry. I. Equilibrium

February 1, 2004
Author(s)
Jonathan E. Guyer, William J. Boettinger, James A. Warren, Geoffrey B. McFadden
A diffuse interface (phase field) model for an electrochemical system is developed. We describe the minimal set of components needed to model an electrochemical interface and present a variational derivation of the governing equations. With a simple set of

Phase Field Modeling of Electrochemistry. II. Kinetics

February 1, 2004
Author(s)
Jonathan E. Guyer, William J. Boettinger, James A. Warren, Geoffrey B. McFadden
The kinetic behavior of the phase field model described in (J.E. Guyer, W.J. Boettinger, J.A. Warren and G. B. McFadden, Phase field modeling of electrochemistry: Equilibrium, unpublished) is explored for advancing (plating) and receding (corroding)

Phase Field Modeling Applied to the Double Layer

May 1, 2002
Author(s)
Jonathan E. Guyer, William J. Boettinger, James A. Warren, Geoffrey B. McFadden
We present the first application of phase field modeling to electrochemistry. A free energy functional that includes the electrostatic effect of charged particles leads to rich interactions between concentration, electrostatic potential, and phase

Model of Electrochemical Double Layer" Using the Phase Field Method

March 20, 2002
Author(s)
William J. Boettinger, Geoffrey B. McFadden, James A. Warren, Jonathan E. Guyer
We present the first application of phase field modeling to electrochemistry. A free energy functional that includes the electrostatic effect of charged particles leads to rich interactions between concentration, electrostatic potential, and phase

Abstracts for the MSEL Assessment Panel, March 2001

January 26, 2001
Author(s)
Leslie E. Smith, Alamgir Karim, Leonid A. Bendersky, C Lu, J J. Scott, Ichiro Takeuchi, Kathleen M. Flynn, Vinod K. Tewary, Davor Balzar, G A. Alers, Stephen E. Russek, Charles C. Han, Haonan Wang, William E. Wallace, Daniel A. Fischer, K Efimenko, Wen-Li Wu, Jan Genzer, Joseph C. Woicik, Thomas H. Gnaeupel-Herold, Henry J. Prask, Charles F. Majkrzak, Norman F. Berk, John G. Barker, Charles J. Glinka, Eric K. Lin, Ward L. Johnson, Paul R. Heyliger, David T. Read, R R. Keller, J Blendell, Grady S. White, Lin-Sien H. Lum, Eric J. Cockayne, Igor Levin, C E. Johnson, Maureen E. Williams, Gery R. Stafford, William J. Boettinger, Kil-Won Moon, Daniel Josell, Daniel Wheeler, Thomas P. Moffat, W H. Huber, Lee J. Richter, Clayton S. Yang, Robert D. Shull, R A. Fry, Robert D. McMichael, William F. Egelhoff Jr., Ursula R. Kattner, James A. Warren, Jonathan E. Guyer, Steven P. Mates, Stephen D. Ridder, Frank S. Biancaniello, D Basak, Jon C. Geist, Kalman D. Migler
Abstracts relating to research and development in the NIST Materials Science and Engineering Laboratory (MSEL) are presented for a poster session to be presented to the 2001 MSEL Assessment Panel.

NCT In-Situ Probes and the MBE Growth of Compound Semiconductors

October 11, 2000
Author(s)
Joseph G. Pellegrino, Jonathan E. Guyer, Donald A. Gajewski
Our research is centered on the use of in-situ measurement probes that monitor semiconductor growth. Our goal is to correlate material parameters observed during growth with device performance. A goal of this presentation is to develop collaborations that

Diffuse Reflectance Spectroscopy for In Situ Process Monitoring and Control During Molecular Beam Epitaxy Growth of InGaAs Pseudomorphic High Electron Mobility Transistors

September 29, 2000
Author(s)
Jonathan E. Guyer, W. F. Tseng, Joseph G. Pellegrino
We report the use of diffuse reflectance spectroscopy for active, closed-loop control of substrate temperature during the growth of a modulation doped heterostructure. Measurement and control of substrate temperature is a common difficulty for molecular

In Situ Diffuse Reflectance Spectroscopy for Measurement and Control of III-V Molecular Beam Epitaxy

March 17, 2000
Author(s)
Jonathan E. Guyer, W. F. Tseng, W. R. Thurber, Eric M. Vogel, Monica D. Edelstein, Donald A. Gajewski, Joseph G. Pellegrino
We report the use of diffuse reflectance spectroscopy for active, closed-loop control of substrate temperature during the growth of a modulation doped heterostructure. Measurement and control of substrate temperature is a common difficulty for molecular

In situ Metrology During the Growth of Compound Semiconductors by Molecular Beam Epitaxy

February 9, 2000
Author(s)
Donald A. Gajewski, Jonathan E. Guyer, Nhan Van Nguyen, Joseph G. Pellegrino
In this poster, we present the optical response of thin film compound semiconductors measured using in situ spectroscopic ellipsometry (SE), at growth temperatures ((180 to 600) 0C), during the growth by molecular beam epitaxy (MBE). We will focus on in