2015/06/30 by Yangchao Shen, Xiang Zhang, Shuaining Zhang +4 · 12 citations
Computer Science · Physics and Astronomy · #Advanced Chemical Physics Studies #Cluster (spacecraft) #Computer network #Computer science #Coupled cluster #Electronic structure #Molecule #Physics #Political science #Quantum #Quantum Computing Algorithms and Architecture #Quantum and electron transport phenomena #Quantum mechanics #Unitary state #physics.atom-ph #physics.chem-ph #physics.comp-ph #quant-ph
paper · pdf · doi:10.1103/physreva.95.020501
published as Phys. Rev. A 95, 020501 (2017) · 6 pages, 4 figures
arxiv created 2016/11/25 · openalex publication_date 2017/02/15 · arxiv updated 2017/03/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In classical computational chemistry, the coupled-cluster ansatz is one of the most commonly used ab initio methods, which is critically limited by its nonunitary nature. The unitary modification as an ideal solution to the problem is, however, extremely inefficient in classical conventional computation. Here, we provide experimental evidence that indeed the unitary version of the coupled-cluster ansatz can be reliably performed in a physical quantum system, a trapped-ion system. We perform a simulation on the electronic structure of a molecular ion (HeH+), where the ground-state energy surface curve is probed, the energies of the excited states are studied, and bond dissociation is simulated nonperturbatively. Our simulation takes advantages from quantum computation to overcome the intrinsic limitations in classical computation, and our experimental results indicate that the method is promising for preparing molecular ground states for quantum simulations.