Iterative quantum-assisted eigensolver

@article{Bharti2021IterativeQE,
  title={Iterative quantum-assisted eigensolver},
  author={Kishor Bharti and Tobias Haug},
  journal={Physical Review A},
  year={2021}
}
The task of estimating ground state and ground state energy of Hamiltonians is an important problem in physics with numerous applications ranging from solid-state physics to combinatorial optimization. We provide a hybrid quantum-classical algorithm for approximating the ground state and ground state energy of a Hamiltonian. The description of the Hamiltonian is assumed to be a linear combination of unitaries. Our algorithm is iterative and systematically constructs the Ansatz using any given… 

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