Probing ground state properties of the kagome antiferromagnetic Heisenberg model using the Variational Quantum Eigensolver

Understand

Finding and probing the ground states of spin lattices, such as the antiferromagnetic Heisenberg model on the kagome lattice (KAFH), is a very challenging problem on classical computers and only possible for relatively small systems.

• We propose using the Variational Quantum Eigensolver (VQE) to find the ground state of the KAFH on a quantum computer.
• We find efficient ansatz circuits and show how physically interesting observables can be measured efficiently.
• To investigate the expressiveness and scaling of our ansatz circuits we used classical, exact simulations of VQE for the KAFH for different lattices ranging from 8 to 24 qubits.