NISQ algorithm for the matrix elements of a generic observable
- URL: http://arxiv.org/abs/2205.10058v2
- Date: Fri, 2 Dec 2022 09:32:07 GMT
- Title: NISQ algorithm for the matrix elements of a generic observable
- Authors: Rebecca Erbanni, Kishor Bharti, Leong-Chuan Kwek, Dario Poletti
- Abstract summary: We present a noisy intermediate scale quantum algorithm for estimating the diagonal and off-diagonal matrix elements of a generic observable in the energy eigenbasis of a given Hamiltonian.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The calculation of off-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
off-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.
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