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Search Publications by: Jonathan E. Guyer (Fed)

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Displaying 26 - 50 of 84

Benchmark Problems for Phase Field Modeling

January 2, 2017
Author(s)
Andrea Jokisaari, P W. Voorhees, Jonathan E. Guyer, James A. Warren, O. G. Heinonen
We present the first set of benchmark problems for phase field models that are being devel- oped by the Center for Heirarchical Materials Design (CHiMaD) and the National Institute of Standards and Technology (NIST). While many scientific research areas

Windowless CdSe/CdTe Solar Cells with Differentiated Back Contacts: J-V, EQE and Photocurrent Mapping

August 26, 2016
Author(s)
Daniel Josell, Ratan K. Debnath, Jong Yoon Ha, Jonathan E. Guyer, Nhan V. Nguyen, M. A. Sahiner, C Reehil, W. A. Manners
This paper presents a study of windowless CdSe/CdTe thin film photovoltaic devices with in-plane patterning at a submicrometer length scale. The photovoltaic cells are fabricated upon two interdigitated comb electrodes pre-patterned at micrometer length

A multicomponent phase-field model for extremely large partition coefficients

January 31, 2014
Author(s)
Michael J. Welland, Dieter Wolf, Jonathan E. Guyer
We develop a multi-component phase-field model specially formulated to robustly simulate concentration variations from molar to atomic magnitudes across an interface, i.e.: partition coefficients in excess of 10 (superscript 10plus23) such as may be the

Backcontact CdSe/CdTE Windowless Solar Cells

February 1, 2013
Author(s)
Donguk Kim, Carlos M. Hangarter, Ratan K. Debnath, Jong Y. Ha, Carlos R. Beauchamp, Matthew D. Widstrom, Jonathan E. Guyer, Nhan Van Nguyen, B. Y. Yoo, Daniel Josell
This paper details the fabrication and properties of CdSe/CdTe thin film photovoltaic devices with a dual back contact geometry. Device fabrication involves cadmium selenide electrodeposition on one of two interdigitated electrodes on a pre-patterned

The Effect of Substrate Material on Silver Nanoparticle Antimicrobial Efficacy

December 1, 2010
Author(s)
Benita Dair, Dave M. Saylor, T. E. Cargal, Grace R. French, Kristen M. Kennedy, Rachel S. Casas, Jonathan E. Guyer, James A. Warren, Steven K. Pollack
With the advent of Nanotechnology, silver nanoparticles increasingly are being used in coatings, especially in medical device applications, to capitalize on their antimicrobial properties. The increased antimicrobial efficacy of nanoparticulate silver

Predicting Microstructure Development During Casting of Drug Eluting Coatings

September 19, 2010
Author(s)
David M. Saylor, Jonathan E. Guyer, Daniel Wheeler, James A. Warren
We have devised a novel diffuse interface formulation to model the development of chem- ical and physical inhomogeneities, i.e. microstructure, during the process of casting drug eluting coatings. These inhomogeneities, which depend on the coating

Three-Dimensionally Structured Thin Film Heterojunction Photovoltaics on Interdigitated Back-Contacts

February 1, 2010
Author(s)
Daniel Josell, Carlos R. Beauchamp, Behrang H. Hamadani, Suyong S. Jung, Jonathan E. Guyer, Abhishek Motayed, Carlos M. Hangarter, Nadine E. Gergel-Hackett, Hua Xu, Nikolai B. Zhitenev
Fabrication and properties of three-dimensionally structured back-contact heterojunction solar cells are described. A variety of devices are explored, all of which were fabricated by electrochemical deposition of a semiconducting material on one of two

Diffusion Under Temperature Gradient: A Phase-field Model Study

August 11, 2009
Author(s)
Rashmi R. Mohanty, Jonathan E. Guyer, Yong Ho Sohn
A diffuse interface model was devised and employed to investigate the effect of thermotransport (a.k.a., thermomigration) process in single-phase and multi-phase alloys of a binary system. Simulation results show that an applied temperature gradient can

FiPy: PDEs in Python

February 23, 2009
Author(s)
Jonathan E. Guyer, Daniel Wheeler, James A. Warren
Partial differential equations (PDEs) are ubiquitous to the mathematical description of physical phenomena. They describe the relationships between functions of more than one independent variable and partial derivatives with respect to those variables

A Finite Volume PDE Solver Using Python (FiPy)

October 16, 2008
Author(s)
Jonathan E. Guyer, Daniel Wheeler, James A. Warren
We present an object oriented partial differential equation (PDE) solver written in Python based on a standard finite volume (FV) approach.The solution of coupled sets of PDEs is ubuquitous in the numerical simulation of science problems. Numerous PDE

Modeling Superconformal Electrodeposition Using an Open Source PDE Solver

October 16, 2008
Author(s)
Daniel Wheeler, Jonathan E. Guyer
Superconformal electrodeposition enables the void-free filling of high aspect ratio features such as trenches or vias in the Damascene metallization process. Superconformal electrodeposition, also known as superfill, occurs when particular combinations of