Spin-projection for quantum computation: A low-depth approach to strong correlation
arXiv:2004.12024 · doi:10.1103/PhysRevResearch.2.043142
Abstract
Although spin is a core property in fermionic systems, its symmetry can be easily violated in a variational simulation, especially when strong correlation plays a vital role therein. In this study, we will demonstrate that the broken spin-symmetry can be restored exactly in a quantum computer, with little overhead in circuits, while delivering additional strong correlation energy with the desired spin quantum number. The proposed scheme permits drastic reduction of a potentially large number of measurements required to ensure spin-symmetry by employing a superposition of only a few rotated quantum states. Our implementation is universal, simple, and, most importantly, straightforwardly applicable to any ansatz proposed to date.
9 pages, 7 figures, 2 tables
References in corpus (2)
Cited by in corpus (12)
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