Matlab code for quantum spin-1/2 networks. It provides code to analyse the geometry of such networks, and some basic quantum control and characterisation code. Details are described in these papers:
F. C. Langbein, S. G. Schirmer, E. Jonckheere. Time optimal information transfer in spintronics networks. Proc. IEEE 54th Annual Conference on Decision and Control (CDC), pp. 6454-6459, Osaka, Japan, December 15-18, 2015. DOI:10.1109/CDC.2015.7403236 arXiv:1508.00928 https://langbein.org/langbein2015/
E. Jonckheere, F. C. Langbein, S. G. Schirmer. Information Transfer Fidelity in Spin Networks and Ring-based Quantum Routers. Quantum Information Processing, 14(12):4761-4785, 2015. DOI:10.1007/s11128-015-1136-4 arXiv:1408.3765 https://langbein.org/jonckheere2015/
S. G. Schirmer, F. C. Langbein. Characterization and Control of Quantum Spin Chains and Rings. In: Proc. 6th Int Symp Communications, Control and Signal Processing (ISCCSP), pp. 615 - 619, May 2014. DOI:10.1109/ISCCSP.2014.6877950 arXiv:1403.0226 https://langbein.org/schirmer2014/
E. Jonckheere, F. C. Langbein, S. Schirmer. Quantum networks: Anti-core of spin chains. Quantum Information Processing. 13(7):1607- 1637, 2014. DOI:10.1007/s11128-014-0755-5 arXiv:1403.0159 https://langbein.org/jonckheere2014/
E. Jonckheere, F. C. Langbein, S. G. Schirmer. Curvature of quantum rings. In: Proc. 5th Int Symp Communications Control and Signal Processing (ISCCSP), pp. 1-6, 2012. DOI:10.1109/ISCCSP.2012.6217863 arXiv:1202.2556 https://langbein.org/jonckheere2012/
E Jonckheere, S G Schirmer, F C Langbein. Geometry and Curvature of Spin Networks. IEEE International Conference on Control Applicatons, pp. 786-791, 2011. DOI:10.1109/CCA.2011.6044395 arXiv:1102.3208 https://langbein.org/jonckheere2011/
To get started, go to the base directory of the package and run
setup('build') from matlab (to compile the code and extend the
setup() without arguments only adds the paths.
Most functionality is provided via the qsn class. See
and the help text for the relevant classes (
help qsn.QSN, etc.)
for further information on how to use the code. The
scripts provide some examples for how to use the code. All this code is
+qsn matlab pacakge directory.
timing directory contains timing estimation code for
reference  above.
Other Software Used
The following matlab packages have been adapted for this package and
are in the
GA sub-directory respectively:
GA - Alan de Freitas, Open Genetic Algorithm Toolbox, 2012. Creative Commons Attribution Non-Commercial License V2.0 https://sourceforge.net/projects/gatoolbox/
@kde - Alexander Ihler, KDE Package, 2003. GNU Lesser General Public License V2.1 https://www.ics.uci.edu/~ihler/code/kde.html
License - AGPL v3.0
Copyright (C) 2011-2019 Frank C Langbein, Cardiff University; Sophie G Shermer, Swansea University; Edmond Jonckheere, USC.
This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License along with this program. If not, see https://www.gnu.org/licenses/.