# Shallow-circuit variational quantum eigensolver based on symmetry-inspired Hilbert space partitioning for quantum chemical calculations

@article{Zhang2020ShallowcircuitVQ, title={Shallow-circuit variational quantum eigensolver based on symmetry-inspired Hilbert space partitioning for quantum chemical calculations}, author={Feng Zhang and Niladri Gomes and Noah F. Berthusen and Peter P. Orth and Caizhuang Wang and Kai‐Ming Ho and Yongxin Yao}, journal={Physical Review Research}, year={2020} }

Development of resource-friendly quantum algorithms remains highly desirable for noisy intermediate-scale quantum computing. Based on the variational quantum eigensolver (VQE) with unitary coupled cluster ansatz, we demonstrate that partitioning of the Hilbert space made possible by the point group symmetry of the molecular systems greatly reduces the number of variational operators by confining the variational search within a subspace. In addition, we found that instead of including all…

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