Quantum orbital-optimized unitary coupled cluster methods in the strongly correlated regime: Can quantum algorithms outperform their classical equivalents?

@article{Sokolov2019QuantumOU,
  title={Quantum orbital-optimized unitary coupled cluster methods in the strongly correlated regime: Can quantum algorithms outperform their classical equivalents?},
  author={Igor O Sokolov and Panagiotis Kl. Barkoutsos and Pauline J. Ollitrault and Donny Greenberg and Julia E. Rice and Marco Pistoia and Ivano Tavernelli},
  journal={The Journal of chemical physics},
  year={2019},
  volume={152 12},
  pages={
          124107
        }
}
The Coupled Cluster (CC) method is used to compute the electronic correlation energy in atoms and molecules and often leads to highly accurate results. However, due to its single-reference nature, standard CC in its projected form fails to describe quantum states characterized by strong electronic correlations and multi-reference projective methods become necessary. On the other hand, quantum algorithms for the solution of many-electron problems have also emerged recently. The quantum unitary… 

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