Variational Quantum Computation of Excited States

  title={Variational Quantum Computation of Excited States},
  author={Oscar Higgott and Daochen Wang and Stephen Brierley},
The calculation of excited state energies of electronic structure Hamiltonians has many important applications, such as the calculation of optical spectra and reaction rates. While low-depth quantum algorithms, such as the variational quantum eigenvalue solver (VQE), have been used to determine ground state energies, methods for calculating excited states currently involve the implementation of high-depth controlled-unitaries or a large number of additional samples. Here we show how overlap… Expand

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