Kagome Lattice State Preparation
New experiment proposal
General details
I would like to contribute my solution to the Open Science prize Kagome Lattice an an experiment. This would be an interesting manual for other types of lattices.
Experiment name
KagomeLatticeExperiment
Experiment type
Quantum ground state preparation using the VQE.

Other: See https://ibmquantumawards.bemyapp.com/#/event
Experiment protocol
Preparing quantum states lies at the heart of quantum computing, and is essential to promising applications of near-term quantum processors. The goal is to prepare the ground state of a Heisenberg spin-1/2 Hamiltonian on a kagome lattice with the highest fidelity using VQE. NOte that this is as described in the Open Science Prize
Experiment analysis
- Prepare the ground state of a Heisenberg spin-1/2 Hamiltonian
- Compute the ground state energy with the highest fidelity using VQE.
- Provide a plot figure if the VQE results within the analysis results.
References
- https://ibmquantumawards.bemyapp.com/#/event
- Spin Liquids in Frustrated Magnets. https://www.nature.com/articles/nature08917
Implementation details
Experiment implementation
- Qiskit Runtime Ansatz library
- Qiskit Runtime Optimizer library
- Inputs: Quantum processor, Transpilation backend, Number of qubits of the QPU, Ansatz type, Optimizer type
Optimizer type
| Name | Description | Default Value |
|---|---|---|
| -o, --optimizer_type | Optimizer type: · SPSA · SLSQP · COBYLA · UMDA · GSLS · GradientDescent · L_BFGS_B · NELDER_MEAD · POWELL · NFT | SPSA |
| -i, --max_iter | Maximum number of iterations or function evals used by the optimizer. | 100 |
Default parameters: • Ansatz: The heuristic excitation-preserving wave function ansatz. ExcitationPreserving (reps=1, entanglement=’linear’) • Optimizer: Simultaneous Perturbation Stochastic Approximation (SPSA) optimizer. SPSA (maxiter=100) • Resilience/Error mitigation: Zero noise extrapolation - ZNE (1). • Shots: 2048 • Edge weight: 1.0 • Heisenberg Model Uniform Interaction: 1.0 • Heisenberg Model Uniform potential: 0.0
Experiment analysis
Plots generated from the energy values returned by the VQE

Workflow
NOTE: An experiment PR failing to complete all the workflow steps below will not be merged!
- [ ] Complete the proposal section above and have your proposal reviewed and approved
- [ ] Open a PR and link it to the new experiment issue
- [ ] Create the main module files (at least one for the experiment and one for its analysis). Place them in the right folders
- [ ] Define and implement the experiments APIs
- [ ] Have the experiment API reviewed and approved
- [ ] Implement all the experiment and analysis functionality
- [ ] Verify that your experiment runs properly on a real device and that the results make sense
- [ ] Verify that your experiment runs properly in the context of a parallel experiment, where sub-experiments run on different qubits. Verify this also on a real device
- [ ] Verify that figures look OK: for regular experiments, parallel experiments, aggregated experiments
- [ ] Verify that experiment data is properly saved to and load from the results DB (experiments service), and that your experiment data is displayed correctly in the results DB webpage
- [ ] Add unit testing for the experiment and analysis classes. If needed implement a mock-backend for your experiment
Include in your testing running the experiment in the context of
ParallelExperiment - [ ] Write API docs for all your API methods. Follow the guideline here
- [ ] Write a user guide for your experiment. Follow the guideline here
- [ ] Add a new release note. Follow the guideline here
- [ ] Ask for a final review for the implementation, documentation and testing
- [ ] Celebrate!
Thanks for suggesting your experiment. We don't currently support Runtime integration, so this will have to be on hold until there's support.