Computing light masks in neutral atom lithography
Abstract
In neutral atom lithography, a collimated beam of atoms is sent through a region of standing light waves created by interfering laser beams. The intensity distribution of the light field modulates the density distribution of the atoms transversal to the beam direction. The atomic beam materializes on a substrate, and the atoms are deposited in a pattern which mimics the intensity distribution of the light. It is thus possible to create nanostructures by a suitable adjustment of the light field. While the computation of the pattern of atoms generated by any given setup of laser beams with known amplitudes and phases is straightforward, the inverse problem of deducting the appropriate amplitude and phase of each single beam to create a prescribed pattern has to our knowledge not yet been addressed. We propose a numerical method to derive these values for a fixed setup of laser beams. We consider first the general case of unrelated beam directions and then specialize to setups which induce periodic patterns. The solution of the inverse problem is a twostep process: we use Fourier techniques to compute a set of characteristic amplitude values which enter the righthand side of a nonlinear system of equations. This systemmore »
 Authors:
 Institute for Computational Engineering and Sciences, University of Texas at Austin, 1 University Station, C0200, Austin, TX 78712 (United States). Email: carsten@ices.utexas.edu
 Institut fuer Numerische Simulation, Universitaet Bonn, Wegelerstrasse 6, 53115 Bonn (Germany). Email: braun@ins.unibonn.de
 Institute for Computational Engineering and Sciences, University of Texas at Austin, 1 University Station, C0200, Austin, TX 78712 (United States). Email: kunoth@ins.unibonn.de
 Publication Date:
 OSTI Identifier:
 20840370
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics; Journal Volume: 220; Journal Issue: 1; Other Information: DOI: 10.1016/j.jcp.2006.07.012; PII: S00219991(06)00341X; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; ATOMIC BEAMS; ATOMS; DENSITY; EQUATIONS; FOURIER TRANSFORMATION; LASERS; MATHEMATICAL SOLUTIONS; NANOSTRUCTURES; NONLINEAR PROBLEMS; PERIODICITY; SUBSTRATES; VISIBLE RADIATION
Citation Formats
Burstedde, Carsten, Braun, Juergen, and Kunoth, Angela. Computing light masks in neutral atom lithography. United States: N. p., 2006.
Web. doi:10.1016/j.jcp.2006.07.012.
Burstedde, Carsten, Braun, Juergen, & Kunoth, Angela. Computing light masks in neutral atom lithography. United States. doi:10.1016/j.jcp.2006.07.012.
Burstedde, Carsten, Braun, Juergen, and Kunoth, Angela. Wed .
"Computing light masks in neutral atom lithography". United States.
doi:10.1016/j.jcp.2006.07.012.
@article{osti_20840370,
title = {Computing light masks in neutral atom lithography},
author = {Burstedde, Carsten and Braun, Juergen and Kunoth, Angela},
abstractNote = {In neutral atom lithography, a collimated beam of atoms is sent through a region of standing light waves created by interfering laser beams. The intensity distribution of the light field modulates the density distribution of the atoms transversal to the beam direction. The atomic beam materializes on a substrate, and the atoms are deposited in a pattern which mimics the intensity distribution of the light. It is thus possible to create nanostructures by a suitable adjustment of the light field. While the computation of the pattern of atoms generated by any given setup of laser beams with known amplitudes and phases is straightforward, the inverse problem of deducting the appropriate amplitude and phase of each single beam to create a prescribed pattern has to our knowledge not yet been addressed. We propose a numerical method to derive these values for a fixed setup of laser beams. We consider first the general case of unrelated beam directions and then specialize to setups which induce periodic patterns. The solution of the inverse problem is a twostep process: we use Fourier techniques to compute a set of characteristic amplitude values which enter the righthand side of a nonlinear system of equations. This system is then solved iteratively by a coordinate descent method.},
doi = {10.1016/j.jcp.2006.07.012},
journal = {Journal of Computational Physics},
number = 1,
volume = 220,
place = {United States},
year = {Wed Dec 20 00:00:00 EST 2006},
month = {Wed Dec 20 00:00:00 EST 2006}
}

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