External Technical Papers
This list of papers provides examples of published research which includes results
from INTEGRATED's software. This is not intended to claim endorsement from the authors, just to
provide samples of work using the software and links to make it easy for you to locate
copies of those papers which would be relevant to your own work.
For copyright reasons the content of these papers is not reproduced on this site. Rather, the provided links
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to access them. The full reference information is also given so that the papers can be located in a library.
Also See: Internal Technical Papers
Improved design of a high-voltage vacuum-insulator interface
PHYSICAL REVIEW SPECIAL TOPICS - ACCELERATORS AND BEAMS 8, 050401 (2005)
W. A. Stygar,1 J. A. Lott,2 T. C. Wagoner,2 V. Anaya,2 H. C. Harjes,1 H. C. Ives,3 Z. R. Wallace,2 G. R. Mowrer,1
R.W. Shoup,1 J. P. Corley,2 R. A. Anderson,1 G. E. Vogtlin,4 M. E. Savage,1 J. M. Elizondo,1 B. S. Stoltzfus,1
D. M. Andercyk,5 D. L. Fehl,1 T. F. Jaramillo,2 D. L. Johnson,6 D. H. McDaniel,1 D. A. Muirhead,1 J. M. Radman,5
J. J. Ramirez,1 L. E. Ramirez,2 R. B. Spielman,1 K.W. Struve,1 D. E. Walsh,7 E. D. Walsh,7 and M. D. Walsh7
1Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
2Ktech Corporation, Albuquerque, New Mexico 87123, USA
3EG&G, Albuquerque, New Mexico 87107, USA
4Lawrence Livermore National Laboratory, Livermore, California 94550, USA
5Trace Laboratories, Hunt Valley, Maryland 21030, USA
6Titan-Pulse Sciences Division, San Leandro, California 94577, USA
7C-Lec Plastics, Philadelphia, Pennsylvania 19135, USA
We have conducted a series of experiments designed to measure the flashover strength of various
azimuthally symmetric 45o vacuum-insulator configurations. The principal objective of the experiments
was to identify a configuration with a flashover strength greater than that of the standard design, which
consists of a 45o polymethyl-methacrylate (PMMA) insulator between flat electrodes. The thickness d and
circumference C of the insulators tested were held constant at 4.318 and 95.74 cm, respectively. The peak
voltage applied to the insulators ranged from 0.8 to 2.2 MV. The rise time of the voltage pulse was 40–
60 ns; the effective pulse width [as defined in Phys. Rev. ST Accel. Beams 7, 070401 (2004)] was on the
order of 10 ns. Experiments conducted with flat aluminum electrodes demonstrate that the flashover
strength of a crosslinked polystyrene (Rexolite) insulator (18 +/- 7)% higher than that of PMMA.
Experiments conducted with a Rexolite insulator and an anode plug, i.e., an extension of the anode into the
insulator, demonstrate that a plug can increase the flashover strength by an additional (44 +/- 11)% The
results are consistent with the Anderson model of anode-initiated flashover, and confirm previous
measurements. It appears that a Rexolite insulator with an anode plug can, in principle, increase the
peak electromagentic power that can be transmitted across a vacuum interface by a factor of
[(1.18)X(1.44)]2 = 2.9 over that which can be achieved with the standard design.
ELECTRIC AND MAGNETIC DESIGN OF THE g-2 MAGNETIC KICKER
APAC98 Proceedings
W. Feng, Nanjing University, Nanjing 210093, China
E. B. Forsyth and G. C. Pappas, Brookhaven National Laboratory, Upton, New York 11973, U.S.A.
The ultra-high precision g-2 experiment requires a fast kicker to deflect incoming muon beam with a momentum
of 3.094 Gev/c. A magnetic kicker was selected since this approach requires the lowest excitation voltage of all
designs considered. However, a higher driving current (>6000A) is required which leads to more residual eddy
current field to influence the main dipole magnetic field. Several possible magnetic kicker designs were
investigated to determine their effects on kicker field quality, driving efficiency (B/I) and inductance per unit
length. A satisfatory construction is a two plate kicker with shaped edges for the two electrodes. Using the
transient eddy current analyses (Opera 2d/TR)[1], the authors studied a variety of factors which affect the eddy
current residual field. This paper presents the electric and magnetic parameters of the magnetic kicker which
was completed in 1996 and has been put into operation now.
* references
ELECTRO for electric field results.
CHARACTERISTICS OF A DUST TRAJECTORY SENSOR
Review of Scientific Instruments, Volume 79, Published: August 4, 2008
Siegfried Auer,1 Eberhard Grün,2,3 Sascha Kempf,3,4 Ralf Srama,3,5 André Srowig,6 Zoltan Sternovsky,2
and Valentin Tschernjawski7
1 A&M Associates, P.O. Box 421, Basye, Virginia 22810, USA
2 LASP, University of Colorado, Boulder, Colorado 80309, USA
3 Max-Planck-Institut für Kernphysik, Heidelberg 69029, Germany
4 Institut für Geophysik und Extraterrestrische Physik, Universität Braunschweig, Braunschweig 38106, Germany
5 Institut für Raumfahrtsysteme, Universität Stuttgart, Stuttgart 70569, Germany
6 ASIC Labor, Universität Heidelberg, Heidelberg 69120, Germany
7 Deutsches Zentrum für Luft-und Raumfahrt, Berlin-Adlershof 12489, Germany
Trajectories of cosmic dust particles are determined by the measurement of the electrical signals that are
induced when a charged grain flies through a position-sensitive electrode system. A typical dust trajectory
sensor has four sensor planes consisting of about 16 wire electrodes each. Two adjacent planes have
orthogonal wire directions. The sensor is highly transparent and mechanically robust, provides a large
sensitive area, large field of view, and can, at least in principle, achieve unlimited precision. While
a sensor model had already undergone limited testing in the dust laboratory, its response as a function
of position and angle of incidence of the trajectory and as a function of sensor dimensions was generally
unknown. To better understand its characteristics, the operation of a sensor model consisting of three
planes and seven wires per plane was simulated using the COULOMB computer program. We show that the
response of the reduced model can be applied to a model with more planes and more wires per plane. The
effect of a trajectory's position and angle on the signal strength is discussed as well as the influence
of geometrical parameters such as wire diameter, distance between wire planes, and wire length. We found
a greater effect of the wire diameter on the signal strength, and a lesser effect of the plane distance,
than expected. A set of similarity rules is provided for the design of a larger sensor. Finally, we
discuss the optimization of the sensor for different applications. ©2008 American Institute of Physics
* COULOMB was used in this work.
Computed Electric Charges of Grains with Highly Irregular Shapes
Workshop on Dust in Planetary Systems (ESA SP-643).
September 26-30 2005, Kauai, Hawaii. Editors: Krueger, H. and Graps, A., p.177-180. Published 2007
Auer, Siegried; Kempf, Sascha; Gruen, Eberhard
The electric charges of highly irregular dust grains were computed. We find that, of all
possible shapes, a sphere carries the lowest charge and "fluffy" grains, especially grains consisting of long rods,
carry charges as high as kappa=30 times the charge of a spherical grain having the same volume and surface potential.
We conclude that one tends to over-estimate a grain's size when deducing it from the grain's charge, unless the shape
factor kappa is taken into account.
* references obtaining results from COULOMB.
Planar Electrode Dielectrophoresis Systems
A Thesis Submitted to the Faculty of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science
The University of Calgary
Lee Fason Hartley
Demand from the biosciences continues to increase for systems able to assist in the
preparation and analysis of biological samples. Appropriately, dielectrophoresis
continues to emerge as a valuable technique for characterizing a diverse array of
particles. Particle processing systems capable of autonomously executing various
operations on samples may offer cost effective means for such tasks. Dielectrophoretic
microelectromechanical systems technology is well positioned to participate in this
growing industry...
* references obtaining results from COULOMB.
Three-dimensional modeling of potential and electric-field distributions along an EHV ceramic post insulator covered with ice - Part I: Simulations of a melting period
IEEE Transactions on Power Delivery
Publication Date: July 2005
Volume: 20, Issue: 3, page(s): 2006- 2013
Volat, C. Farzaneh, M.
Univ. of Quebec-Chicoutimi, Chicoutimi, Que., Canada;
The main objective of this paper is to determine the potential and
electric-field distributions along a typical ceramic extremely-high-voltage post
insulator covered with atmospheric ice during a melting period. Commercial
software, Coulomb 3D, based on the boundary element method (BEM), was used for
all of the three-dimensional modeling and simulations. It was demonstrated that
the BEM is well suited for evaluating the effect of ice shedding on the
potential and electric-field distributions along an ice-covered insulator during
a melting period. The results obtained show that the length and number of ice
free zones, also called air gaps, are the major parameters that affect the
applied voltage distribution along an ice-covered insulator. The mean electric
field per arcing distance, affected mainly by the air-gap lengths, can provide a
good indication of the presence of partial arcing along the different air gaps.
* references obtaining results from COULOMB.
Five parametric resonances in a microelectromechanical system
Letters to Nature
NATURE | VOL 396 | 12 NOVEMBER 1998
Kimberly L. Turner*, Scott A. Miller²³, Peter G. Hartwell§,
Noel C. MacDonald§, Steven H. Strogatz* & Scott G. Adams*²
* Department of Theoretical and Applied Mechanics, ² School of Applied and
Engineering Physics, § School of Electrical Engineering and the Cornell
Nanofabrication Facility, Cornell University, Ithaca, New York 14853-5401, USA
³ Present address: Kionix, Inc., 22 Thornwood Drive, Ithaca, New York 14850, USA.
The Mathieu equation governs the forced motion of a swing, the
stability of ships and columns, Faraday surface wave patterns on
water, the dynamics of electrons in Penning traps, and the
behaviour of parametric amplifiers based on electronic or superconducting
devices. Theory predicts that parametric resonances
occur near drive frequencies of 2v0=n, where v0 is the system's
natural frequency and n is an integer >1. But in macroscopic
systems, only the first instability region can typically be observed,
because of damping and the exponential narrowing of the
regions with increasing n. Here we report parametrically excited
torsional oscillations in a single-crystal silicon microelectromechanical
system. Five instability regions can be measured, due to the
low damping, stability and precise frequency control achievable in
this system. The centre frequencies of the instability regions agree
with theoretical predictions. We propose an application that uses
parametric excitation to reduce the parasitic signal in capacitive
sensing with microelectromechanical systems. Our results suggest
that microelectromechanical systems can provide a unique testing
ground for dynamical phenomena that are difficult to detect in
macroscopic systems.
* this paper uses COULOMB for electrostatic force and torque computations.
Passive superconducting shielding: experimental results and computer models
AIP Conference Proceedings -- June 23, 2004 -- Volume 710, pp. 1754-1762
ADVANCES IN CRYOGENIC ENGEINEERING: Transactions of the Cryogenic Engineering Conference - CEC
B. A. Warner and K. Kamiya
Cryogenics Branch, Goddard Space Flight Center, Greenbelt, Maryland 20771
Tsukuba Magnet Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0003, Japan
Passive superconducting shielding for magnetic refrigerators has advantages over active shielding and
passive ferromagnetic shielding in that it is lightweight and easy to
construct. However, it is not as easy to model and does not fail gracefully.
Failure of a passive superconducting shield may lead to persistent flux and
persistent currents. Unfortunately, modeling software for superconducting
materials is not as easily available as is software for simple coils or for
ferromagnetic materials. This paper will discuss ways of using available
software to model passive superconducting shielding.
Progress on a 4 K to 10 K Continuously Operating Adiabatic Demagnetization Refrigerator
AIP Conference Proceedings -- April 27, 2006 -- Volume 823, pp. 969-976
ADVANCES IN CRYOGENIC ENGINEERING: Transactions of the Cryogenic Engineering Conference - CEC
M. DiPirro, J. Tuttle, M. Jackson, E. Canavan, B. Warner, and P. Shirron
NASA/Goddard Space Flight Center, Code 552, Greenbelt, MD 20771
An adiabatic demagnetization refrigerator (ADR) is under development for use in cooling
relatively large loads (10–100 mW) at 4 K and rejecting that heat to a cryocooler operating at 10 K.
ADRs can operate in this temperature range with an efficiency of 75% of Carnot, saving as much as 2/3
of the required overall input power. In addition this ADR can provide cooling down to 0.4 K. The ADR
magnet consists of 8 short coils wired in series and arranged in a toroid to provide self-shielding
of its magnetic field. Eliminating passive or active shields saves 30% of the mass of the system.
The average field is 3 Tesla using 5 amps. In the first model the coils are wound with ordinary NbTi
superconducting wire and operated at 4 K. A second version will then use fine Nb3Sn wire to provide
complete 10 K operation. As a refrigerant for this temperature range we are using readily available
gadolinium gallium garnet (GGG) crystals, which provide suitable performance. In the future we will
switch to either GdLiF4 or GdF3, which have 13% or 30%, respectively, more cooling power per volume
than GGG. We use gas gap heat switches to alternately connect the toroid to the cold load and the
warm heat sink. A small continuous stage maintains the cold end at 4 K while the main toroid is
recycled. Data on toroid , magnet performance with respect to central field vs. current and fringing
field vs. current are given. Data on the transient heating due to hysteresis losses within the
superconductor are also presented.
* although it isn't mentioned by name,
AMPERES produced
all 3D magnetic modeling presented in this paper
Chicane compressor development for BNL ATF- applications to SASE FEL
conference: 22nd International Free Electron Laser Conference
year published: 2001
year authored: 2000
R. Agustsson,J. Rosenzweig
A chicane compressor is being designed and constructed at UCLA for implementation at the BNL Accelerator
Test Facility. The beam optics, including collective fields, and expected performance of the device has been
simulated using TRACE3D and ELEGANT. Based on these studies, as well as constraints due to downstream ATF
optics, the chicane magnet specifications were determined. The dipole magnets were designed using AMPERES
3D magnetostatic modeling, and have been constructed. Implementation of this device at the ATF, as well
as initial physics experiments on coherent synchrotron radiation emission (and associated emittance growth)
at 70 MeV, and expected performance enhancement of the VISA SASE FEL experiment, are discussed.
A method to obtain uniform magnetic-field energy density gradient distribution using discrete pole pieces for a microelectromechanical-system-based magnetic cell separator
J. Appl. Phys. 99, 08R905 (2006)
Pulak Nath
Biomedical Engineering, The Cleveland Clinic Foundation, Cleveland, Ohio 44195 and Department of Chemical and Biomedical Engineering, Cleveland State University, Cleveland, Ohio 44115
Lee R. Moore, Maciej Zborowski, Shuvo Roy, and Aaron Fleischman
Biomedical Engineering, The Cleveland Clinic Foundation, Cleveland, Ohio 44195
A spatially uniform magnetic energy density gradient (delB2) distribution offers a
controlled environment to separate magnetically tagged cells or biomolecules based on their magnetophoretic
mobility [L. R. Moore et al., J. Biochem. Biophys. Methods 37, 11 (1998)]. A design to obtain a uniform delB2
distribution for a microelectromechanical-systems-based magnetic cell separator was developed. The design
consists of an external magnetic circuit and a microfabricated channel (biochip) with embedded discrete
pole pieces on the channel walls. The two-dimensional and three-dimensional magnetostatic simulation
softwares utilizing boundary element methods were used to optimize the positions and the dimensions of the
discrete pole pieces, as well as the external magnetic circuit—the combination of which would generate a
uniform delB2 profile over the channel cross section. It was found that the discrete pole
pieces required specific magnetic properties (saturation magnetization constant >1.55 T) to affect the
overall delB2 distribution. Investigating different positions of the discrete pole
pieces inside the external magnetic field indicated that the proposed design could generate uniform delB2
distribution with ±100 µm displacements along the height/width and ±1° inclination from the optimum position.
Design studies for a H- ion extraction system
Review of Scientific Instruments -- May 2004 -- Volume 75, Issue 5, pp. 1783-1785
A. Ushakov, K. Volk, H. Klein, and U. Ratzinger
Institut für Angewandte Physik, Universität Frankfurt, Robert-Mayer-Strasse 2-4, 60054 Frankfurt, Germany
At the University of Frankfurt, a high current H- ion source was developed and tested.
A H– beam current of 120 mA with an energy of 35 keV was extracted using an emission opening radius of 5 mm.
This source was equipped with a diode extraction system. Thus, the extraction voltage determines the beam energy,
depending on the plasma density. In order to adjust the extraction voltage independently from the beam energy,
a 65 kV extractor is being designed. It consists of a compact four electrode (tetrode) system. The electron dumping
will be performed after the tetrode system. For computing three dimensional magnetic field distributions the code
AMPERES has been used. The influence of magnetic fields on the beam path has been taken into account. The article
presents the layout of a compact 65 kV extractor for 120 mA H-.
Magnetic cross-talk compensation for an optical current transducer
IEEE Transactions on Instrumentation and Measurement, Vol.50, No.5, pp.1071-1075, 2001.
P. Niewczas, W.I. Madden, W.C. Michie, A. Cruden and J.R McDonald
In this paper, we analyze the errors associated with magnetic crosstalk within point type,
or unlinked, optical current transducers (OCTs) working in a three-phase electric current
transmission systems. For many practical conductor arrangements, the magnetic crosstaIk may
introduce errors unacceptable for the accuracy requirements demanded from the OCT. A solution
to this problem is devised around a unique compensation method which solves, in real time, a set
of linear equations, each representing the instantaneous output signal from one phase current sensor.
Faraday shielding in coaxial winding transformer
International Journal of Applied Electromagnetics and Mechanics
Issue: Volume 11, Number 4 / 2000
Pages: 261 - 267
Junwei Lu and Fu Wong
School of Microelectronic Engineering, Faculty of Engineering, Griffith University, Queensland Australia
This paper presents the configuration of a high frequency (HF) coaxial winding transformer with Faraday
shield and discusses the shielding effect of the transformer in the high frequency range. The experimental
results show the voltage ratio, coupling coefficient and load characteristic of the HF coaxial transformer
in the range up to 2 MHz. The numerical result illustrates the eddy current distribution in the windings
and shielding coil, and the magnetic flux distribution in the shielded HF coaxial transformer.
Studies on Geometries for Inducing Homogeneous Magnetic Fields in the
Application of Real Time Imaging of Steel Reinforcing Bars Embedded Within Pre-Stressed and Reinforced Concrete
AIP Conference Proceedings -- March 6, 2006 -- Volume 820, pp. 1298-1304
QUANTITATIVE NONDESTRUCTIVE EVALUATION
S. Quek, D. Benitez, P. Gaydecki, and V. Torres
School of Electrical and Electronic Engineering, The University of Manchester, PO Box 88, Manchester, M60 1QD, United Kingdom
This paper addresses fundamental issues associated with the
development of a real time inductive scanning system for
non-destructive testing of pre-stressed and reinforced concrete.
Simulated results has indicated that given a coil dimension of
300mm×300mm×2.5mm, 10mm rebars can be imaged down to a depth of 100
mm. Studies also indicate that the vertical component of the induced
magnetic field is most favourable as it can be readily reconstructed
to yield geometryand dimensional information pertaining to the rebar structure.
The Application of Magneto Inductive Sensors for Non-Destructive Testing of
Steel Reinforcing Bars Embedded Within Pre-Stressed and Reinforced Concrete
AIP Conference Proceedings -- March 6, 2006 -- Volume 820, pp. 1284-1289
QUANTITATIVE NONDESTRUCTIVE EVALUATION
D. S. Benitez, S. Quek, P. Gaydecki, V. Torres, and B. Fernandes
Sensing, Imaging and Signal Processing Group (SISP), School of Electrical and Electronic Engineering. The University of Manchester, PO Box 88, Manchester M60 1QD, United Kingdom
This paper demonstrates the feasibility of using solid-state magneto-inductive probes for
detecting and imaging of steel reinforcing bars embedded within pre-stressed and reinforced concrete.
Changes in the inductance of the sensor material are directly proportional to the strength of the
measured magnetic field parallel to the sensor. Experimental results obtained by scanning steel
bars specimens are presented. General performance characteristics and sensor output limitations
are investigated by using different orientations, sensing distance, excitation intensity, bar
sizes and geometries.
Particle Trajectory Analysis
Electron Optics Simulation Software at NUS
H. Q. Hoang, M. Osterberg, and A. Khursheed
Department of Electrical and Computer Engineering, National University of Singapore,
4 Engineering Drive 3, Singapore 117576
hunghq@nus.edu.sg
LORENTZ is demonstrated as a simulation tool by NUS at the Eighth International Conference on Charged Particle Optics, July 2010.
Please see page 221 of the conference handbook for the Electron Optics Simulation Software at NUS article.
Phase-contrast x-ray imaging with a liquid-metal-jet-anode microfocus source
Appl. Phys. Lett. 91, 074104 (2007)
T. Tuohimaa, M. Otendal, and H. M. Hertz
Phase-contrast methods increase contrast, detail, and selectivity in x-ray imaging. Present compact x-ray
sources do not provide the necessary spatial coherence with sufficient power to allow the laboratory-scale high-resolution
phase-contrast imaging with adequate exposure times. In this letter, the authors demonstrate phase-contrast imaging with
few-micron detail employing a compact ~6.5 µm spot liquid-metal-jet-anode high-brightness microfocus source. The 40 W source
is operated at more than ten times higher electron-beam power density than present microfocus sources and is shown to provide
sufficient spatial coherence as well as scalability to high power, thereby enabling the application of phase-contrast x-ray
imaging with short exposure times in clinics and laboratories.
High-intensity electron beam for liquid-metal-jet anode hard x-ray generation
Proceedings of SPIE
Laser-Generated, Synchrotron, and Other Laboratory X-Ray and EUV Sources, Optics, and Applications II
Volume 5918 (Sep. 10, 2005)
Tomi Tuohimaa, Mikael Otendal, and Hans M. Hertz
We report on our progress towards the experimental realization of a liquid-metal-jet-anode
x-ray source with high brightness. We have previously shown that this electron-impact source has potential for very
high x-ray brightness by combining small-spot high-flux operation of the electron beam with high-speed operation of
the regenerative liquid-metal-jet anode. In the present paper we review the system and describe theoretical calculations
for improving the 50 kV, 600 W electron-beam focussing to ~30 µm spot size. With such a system the power density on the
liquid-metal-jet would be ~400 kW/mm2, i.e., more than an order of magnitude higher than the power density on a
state-of-the-art rotating anode.
Modeling of a High Current H- LEBT with the Lorentz-EM 3D Ion Optics Code
AIP Conf. Proc. -- August 10, 2007 -- Volume 925, pp. 318-323
PRODUCTION AND NEUTRALIZATION OF NEGATIVE IONS AND BEAMS: 11th International Symposium on the Production and Neutralization of Negative Ions and Beams
Issue Date: August 10, 2007
S. K. Hahto, D. G. Bilbrough, R. Keller
High current electrostatic Low-Energy Beam Transport (LEBT) systems are currently being
developed for several applications ranging from H- cyclotrons to high intensity linear accelerators. A new design
building on the experiences gained from the Spallation Neutron Source (SNS) LEBT system was modeled recently in
2D with PBGUNS. In this paper a 3D treatment is given for this new LEBT design for a 60 mA, 65 kV H- beam. For
this type of LEBT 3D modeling is essential to accurately model the deflection of the co-extracted electrons from
the beam. The beam chopping and steering for RFQ injection also presents a 3D problem for the otherwise
cylindrically symmetric geometry. The modeled LEBT can transport a 60 mA H- beam with 0.2 mm mrad 1-rms emittance
and Twiss parameters that are in accordance with established SNS LEBT specifications.
Fabrication and characterization of nanoelectronic devices for electron beam lithography applications
A Dissertation Presented for the Doctor of Philosophy Degree
The University of Tennessee, Knoxville
May 2005
Xiaojing Yang
Vertically aligned carbon nanofibers (VACNFs) have shown promise for use as
field emission electron sources. Dual-gate field emission structures (triodes) have been
fabricated and characterized. The electron beams can be successfully focused in these
triodes. These studies show VACNF based field emission devices are promising for
electron beam lithography applications. In this thesis, work is continued on triode device
investigation. Methods to improve the device fabrication, to understand/optimize the
device performance, and to repair defective triodes are presented...
Towards coherent control of supersonic beams: a new approach to atom optics
New Journal of Physics 8 (2006), 77
A Libson 1, M Riedel 1, G Bronshtein 2, E Narevicius 1, U Even 2 and M G Raizen 1
1 Center for Nonlinear Dynamics and Department of Physics,The University of Texas at Austin, Austin, TX 78712-1081, USA
2 Sackler School of Chemistry, Tel-Aviv University, Tel-Aviv, Israel
A supersonic beam of noble gas atoms is a source of unprecedented
brightness. A novel short pulse supersonic nozzle is developed with beam intensity
that is higher by at least an order of magnitude than other available sources. We
show how this beam can be coherently slowed and focused using elastic reflection
from single crystals. Simulations show beam fluxes of 1011 atoms s-1 at velocities
of 50ms-1 and temperatures of less than 20 µK in the longitudinal direction.
Possible applications of this slow beam to the study of atom–surface interactions
and atom interferometry are discussed.
* although LORENTZ
isn't mentioned by name, reference 11 states that Integrated Engineering Software was used for simulations
Gas delivery and virtual process chamber concept for gas-assisted material processing in a focused ion beam system
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer
Structures -- November 2004 -- Volume 22, Issue 6, pp. 3008-3011
Valery Ray
Particle Beam Systems & Technology, 290 Broadway Street, Suite 298, Methuen, Massaschusetts 01844
Gas-assisted etching and material deposition using gaseous precursors have become a critical
part of integrated circuit modification and other applications of focused ion beam (FIB) systems. Widely used
methods of gas injection in FIB systems are either needle-type or shroud-type gas delivery nozzles. Each of these
methods of gas delivery has significant drawbacks. Release of the gas from the needle-type nozzles is detrimental
for the vacuum level in the main chamber of the system, as the gas quickly dissipates from the process area.
Insertion of shroud concentrators into the primary ion beam path and the path of secondary electrons leads to a
significant decline in the signal-to-noise ratio of the FIB image. Proposed "CUPOLA" geometry of the gas delivery
nozzle could allow one to effectively concentrate process gas in the area of interest, as is currently done by
shroud concentrators, and, according to secondary-electron trajectory simulations, would significantly improve the
signal level of the secondary-electron image, as compared to the shroud concentrators.
Vertically aligned carbon nanofiber-based field emission electron sources with an integrated focusing electrode
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer
Structures -- January 2004 -- Volume 22, Issue 1, pp. 35-39
M. A. Guillorn, X. Yang, A. V. Melechko, D. K. Hensley, M. D. Hale, V. I. Merkulov, and M. L. Simpson
Molecular-Scale Engineering and Nanoscale Technologies Research Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
L. R. Baylor and W. L. Gardner
Fusion Energy Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
D. H. Lowndes
Thin Film and Nanostructured Materials Physics Research Group, Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
We report on the design, fabrication, and initial characterization of vertically aligned carbon
nanofiber-based microfabricated field emission devices with an integrated out-of-plane electrostatic focusing
electrode. The potential placed on this electrode was found to have a profound impact on the diameter of the beam
emitted from the device as observed on a phosphor screen. Aspects of the device fabrication process and device
operation are discussed. The experimental results obtained are compared to a numerical simulation of device
performance and found to be within good agreement.
Visualizing Field Perturbations With 3-D EM Software
EE - Evaluation Engineering, April 2006
Once out of the question due to cost and time, 3-D EM software now can provide better
visualization of wave dynamics.