The Electron Density: A Fidelity Witness for Quantum Computation

Electron densities calculated using physical (superconducting qubits) and simulated quantum computers for the hydrogen molecule (H2), lithium hydride (LiH), di-lithium (Li2), and hydrogen cyanide (HCN). Additionally, the reduced one-particle density matrix (1-RDM) and results of topological analysis for the mentioned molecules. Calculations on physical quantum hardware were performed on Särimner, a quantum processor with three superconducting qubits. Simulations of quantum computers were performed with Qiskit.