cda-tum / mqt-limdd

MQT LIMDD - A quantum circuit simulator based on decision diagrams written in C++

Important

This simulator uses LIMDD type decision diagrams which only cover a subset of functionality available in mqt-ddsim and mqt-core.

A tool for classical quantum circuit simulation developed as part of the Munich Quantum Toolkit (MQT)¹ by the Chair for Design Automation at the Technical University of Munich. It builds upon MQT Core, which forms the backbone of the MQT.

Usage

The simulator comes with a stand alone executable that takes input via the command line and output their results as json object.

The following example assumes the simulator has been build from source in the build/ directory. Afterwards, there will be an executable ddsim_simple in build/apps/ which can be used to simulate (among others) OpenQASM files. All executables support the --help parameter to list their options.

build/apps/ddsim_simple --help
MQT LIMDD by https://www.cda.cit.tum.de/ -- Allowed options:
  -h [ --help ]          produce help message
  --shots arg            number of measurements (if the algorithm
                         does not contain non-unitary gates, weak
                         simulation is used) (default: 0)
  --ps                   print simulation stats (applied gates, sim.
                         time, and maximal size of the DD)
  --simulate_file arg    simulate a quantum circuit given by file
                         (detection by the file extension)
[...]

build/apps/ddsim_simple --shots 1000 --ps --simulate_file path/to/ghz_03.qasm
{
  "statistics": {
    "applied_gates": 3,
    "approximation_runs": "0",
    "benchmark": "ghz_03",
    "distinct_results": 2,
    "final_fidelity": "1.000000",
    "max_nodes": 7,
    "n_qubits": 3,
    "seed": "0",
    "shots": 1000,
    "simulation_time": 0.00044452399015426636,
    "single_shots": "1",
    "step_fidelity": "1.000000"
  }
}

References

L. Vinkhuijzen, T. Grurl, S. Hillmich, S. Brand, R. Wille, and A. Laarman. Efficient implementation of LIMDDs for quantum circuit simulation. In International Symposium on Model Checking of Software (SPIN), 2023. DOI: 10.1007/978-3-031-32157-3_1

Footnotes

1. The Munich Quantum Toolkit was formerly known under the acronym JKQ and developed by the Institute for Integrated Circuits at the Johannes Kepler University Linz). ↩