Extended wavefunctions for the Variational Quantum Eigensolver
Francesco Benfenati, Leonardo Guidoni, et al.
QIM 2019
We introduce a quantum Monte Carlo inspired reweighting scheme to accurately compute energies from optimally short quantum circuits. This effectively hybrid quantum-classical approach features both entanglement provided by a short quantum circuit, and the presence of an effective nonunitary operator at the same time. The functional form of this projector is borrowed from classical computation and is able to filter out high-energy components generated by a suboptimal variational quantum heuristic Ansatz. The accuracy of this approach is demonstrated numerically in finding energies of entangled ground states of many-body lattice models. We demonstrate a practical implementation on IBM quantum hardware up to an 8-qubit circuit.
Francesco Benfenati, Leonardo Guidoni, et al.
QIM 2019
Panagiotis Kl. Barkoutsos, Fotios Gkritsis, et al.
Chemical Science
Panagiotis Kl. Barkoutsos, Giacomo Nannicini, et al.
Quantum
Alexandre Choquette, Agustin Di Paolo, et al.
PRResearch