Munich Nanotech Toolkit (MNT) Plugins for SiQAD

This provides three Physical Simulators for Silicon Dangling Bond (SiDB) Logic: ClusterComplete, QuickExact and QuickSim.

General information:

Each of these is implemented on top of the fiction framework. This project makes the simulators available inside the SiQAD GUI.

ClusterComplete

ClusterComplete is an exact simulator, i.e., it determines all physically valid charge configurations of a given layout with 100% accuracy.

• The pre-simulation step offers configurability over some of its filtering endeavors: Witness partitioning limit and Overlapping witness limit (always smaller or equal than the former) control limits before an NP-complete sub-problem is being solved. The default values ensure that the factorial scaling in the latter parameter is not noticeable in the total runtime. For large simulation problems, it may be beneficial to raise these parameters---their effect can be quickly observed by setting Show pre-simulation statistics to 1 (on). This reveals a number that is proportional to the total runtime, and might be lowered for the given simulation problem when the aforementioned limits are raised.
• The Instance count parameter gives control over the number of threads used for the simulation. When set to -1, ClusterComplete maximizes computational resources by utilizing all available threads, optimizing simulation efficiency.

QuickExact

QuickExact is an exact simulator, i.e., it determines all physically valid charge configurations of a given layout with 100% accuracy.

• The parameter Simulation base number autodetection determines whether the simulation should automatically assess and set the required base number before starting. When set to 0 (off), this feature is disabled. However, when set to 1 (on), the simulation evaluates the possibility of positively charged SiDBs occurring based on the provided physical parameters or the proximity of SiDBs. If there's a potential for positively charged SiDBs, the base number is dynamically set to 3. Otherwise, it is set to 2. This ensures that the simulation consistently delivers correct results.

QuickSim

QuickSim is an approximate 2-state simulator for determining the ground state of a given SiDB layout.

• It enables the tuning of several simulation parameters: Iteration steps and Alpha. For gate layouts, there should be no need to adjust the default values. If no solution is found, however, Iteration steps can be increased or Alpha reduced to enable high-effort simulation.
• The Instance count parameter gives control over the number of threads used for the simulation. When set to -1, QuickSim maximizes computational resources by utilizing all available threads, optimizing simulation efficiency.

Quick Start

All you need is a git client, cmake, the Boost libraries, and a modern C++ compiler.

Building the Plugins

Clone the repository and its submodules:

bash git clone --recursive https://github.com/cda-tum/mnt-siqad-plugins.git

Inside the newly cloned mnt-siqad-plugins folder, trigger the build process:

bash cmake . -B build cd build cmake --build . -j4 # replace "4" with the number of CPU cores you want to use for the build process

Building a faster ClusterComplete binary

ClusterComplete can be made significantly faster by passing -DFICTION_ENABLE_JEMALLOC=ON, i.e.: bash cmake . -B build -DFICTION_ENABLE_JEMALLOC=ON cd build cmake --build . -j4 NB: This CMake option should not be passed when building QuickSim as it has an adverse effect on the runtime for this plugin. Find more information here.

Using ClusterComplete, QuickExact and QuickSim in the SiQAD GUI

Make sure you have SiQAD installed and the plugins compiled.

Navigate to <PATH-TO-SIQAD>/plugins/ and create new folders named clustercomplete, quicksim and quickexact.

Move the clustercomplete, quicksim and quickexact binaries along with their respective .physeng files from the mnt-siqad-plugins/build/ directory to the newly created siqad/plugins/quicksim/ and siqad/plugins/quickexact/ directories. Once completed, restart SiQAD.

ClusterComplete, QuickExact and QuickSim are now available in the engine list.

References

If you use QuickExact or QuickSim in your work, we would appreciate it if you cite the following publication:

```bibtex @inproceedings{drewniok2023quicksim, author={Drewniok, Jan and Walter, Marcel and Hang Ng, Samuel Sze and Walus, Konrad and Wille, Robert}, title={{\emph{QuickSim}: Efficient \emph{and} Accurate Physical Simulation of Silicon Dangling Bond Logic}}, year={2023}, pages={817-822}, doi={10.1109/NANO58406.2023.10231266}}

@inproceedings{drewniok2024quickexact, author={Drewniok, Jan and Walter, Marcel and Wille, Robert}, title={{The Need for Speed: Efficient Exact Simulation of Silicon Dangling Bond Logic}}, booktitle={Asia and South Pacific Design Automation Conference (ASP-DAC)}, year={2024}} ```