Report on scipost_202211_00047v1
Rebecca Erbanni, Kishor Bharti, L. C. Kwek, Dario Poletti · 2023
The calculation of o↵-diagonal matrix elements has various applications in fields such as nuclear physics and quantum chemistry.In this paper, we present a noisy intermediate scale quantum algorithm for estimating the diagonal and o↵-diagonal matrix elements of a generic observable in the energy eigenbasis of a given Hamiltonian.Several numerical simulations indicate that this approach can find many of the matrix elements even when the trial functions are randomly initialized across a wide range of parameter values without, at the same time, the need to prepare the energy eigenstates.