UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Scalable Quantum Simulation of Molecular Energies

O'Malley, PJJ; Babbush, R; Kivlichan, ID; Romero, J; McClean, JR; Barends, R; Kelly, J; ... Martinis, JM; + view all (2016) Scalable Quantum Simulation of Molecular Energies. PHYSICAL REVIEW X , 6 (3) 10.1103/PhysRevX.6.031007. Green open access

[thumbnail of PhysRevX.6.031007.pdf]
PhysRevX.6.031007.pdf - Published Version

Download (1MB) | Preview


We report the first electronic structure calculation performed on a quantum computer without exponentially costly precompilation. We use a programmable array of superconducting qubits to compute the energy surface of molecular hydrogen using two distinct quantum algorithms. First, we experimentally execute the unitary coupled cluster method using the variational quantum eigensolver. Our efficient implementation predicts the correct dissociation energy to within chemical accuracy of the numerically exact result. Second, we experimentally demonstrate the canonical quantum algorithm for chemistry, which consists of Trotterization and quantum phase estimation. We compare the experimental performance of these approaches to show clear evidence that the variational quantum eigensolver is robust to certain errors. This error tolerance inspires hope that variational quantum simulations of classically intractable molecules may be viable in the near future.

Type: Article
Title: Scalable Quantum Simulation of Molecular Energies
Open access status: An open access version is available from UCL Discovery
DOI: 10.1103/PhysRevX.6.031007
Publisher version: https://doi.org/10.1103/PhysRevX.6.031007
Language: English
Additional information: © 2017 American Physical Society
Keywords: Science & Technology, Physical Sciences, Physics, Multidisciplinary, Physics, COUPLED-CLUSTER METHOD, SUPERCONDUCTING CIRCUIT, CHEMISTRY, COMPUTATION
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry
URI: https://discovery.ucl.ac.uk/id/eprint/1509328
Downloads since deposit
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item