Variational quantum algorithms for discovering Hamiltonian spectra

  title={Variational quantum algorithms for discovering Hamiltonian spectra},
  author={Suguru Endo and Tyson Jones and Sam McArdle and Xiao Yuan and Simon C. Benjamin},
  journal={Physical Review A},
Calculating the energy spectrum of a quantum system is an important task, for example to analyse reaction rates in drug discovery and catalysis. There has been significant progress in developing algorithms to calculate the ground state energy of molecules on near-term quantum computers. However, calculating excited state energies has attracted comparatively less attention, and it is currently unclear what the optimal method is. We introduce a low depth, variational quantum algorithm to… 

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