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arXiv · 1908.05238

A Method of Determining Excited-States for Quantum Computation

P. Jouzdani·S. Bringuier·M. Kostuk
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Abstract

A method is presented in which the ground-state subspace is projected out of a Hamiltonian representation. As a result of this projection, an effective Hamiltonian is constructed where its ground-state coincides with an excited-state of the original problem. Thus, low-lying excited-state energies can be calculated using existing hybrid-quantum classical techniques and variational algorithm(s) for determining ground-state. The method is shown to be fully valid for the H2 molecule. In addition, conditions for the method's success are discussed in terms of classes of Hamiltonians.

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P. Jouzdani, S. Bringuier, M. Kostuk. 2019-08-12. A Method of Determining Excited-States for Quantum Computation. https://doi.org/10.1557/s43580-021-00111-3

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