Enhancing the Electron Pair Approximation with Measurements on Trapped Ion Quantum Computers (2312.05426v1)
Abstract: The electron pair approximation offers a resource efficient variational quantum eigensolver (VQE) approach for quantum chemistry simulations on quantum computers. With the number of entangling gates scaling quadratically with system size and a constant energy measurement overhead, the orbital optimized unitary pair coupled cluster double (oo-upCCD) ansatz strikes a balance between accuracy and efficiency on today's quantum computers. However, the electron pair approximation makes the method incapable of producing quantitatively accurate energy predictions. In order to improve the accuracy without increasing the circuit depth, we explore the idea of reduced density matrix (RDM) based second order perturbation theory (PT2) as an energetic correction to electron pair approximation. The new approach takes into account of the broken-pair energy contribution that is missing in pair-correlated electron simulations, while maintaining the computational advantages of oo-upCCD ansatz. In dissociations of N$_2$, Li$_2$O, and chemical reactions such as the unimolecular decomposition of CH$_2$OH$+$ and the \snTwo reaction of CH$_3$I $+$ Br$-$, the method significantly improves the accuracy of energy prediction. On two generations of the IonQ's trapped ion quantum computers, Aria and Forte, we find that unlike the VQE energy, the PT2 energy correction is highly noise-resilient. By applying a simple error mitigation approach based on post-selection solely on the VQE energies, the predicted VQE-PT2 energy differences between reactants, transition state, and products are in excellent agreement with noise-free simulators.
- Y. Cao, J. Romero, J. P. Olson, M. Degroote, P. D. Johnson, M. Kieferová, L. D. Kivlichan, T. Menke, B. Peropadre, N. P. D. Sawaya, S. Sim, L. Veis, and A. Aspuru-Guzik, “Quantum Chemistry in the Age of Quantum Computing,” Chem. Rev. 119, 10856–10915 (2019).
- E. Farhi, J. Goldstone, and S. Gutmann, “A Quantum Approximate Optimization Problem,” arXiv preprint arXiv:1411.4028v1 (2014).
- M. Benedetti, E. Lloyd, S. Sack, and M. Fiorentini, “Parametrized Quantum Circuits as Machine Learning Models,” Quantum Sci. Technol. 4, 043001 (2019).
- Attila Szabo and Neil S. Ostlund, Modern Quantum Chemistry: Introduction to Advanced Electronic Structure Theory (Dover Publications, Mineola, N.Y., 1996).
- B. Bauer, S. Bravyi, M. Motta, and G. K-L. Chan, “Quantum Algorithms for Quantum Chemistry and Quantum Materials Science,” Chem. Rev. 120, 12685–12717 (2020).
- J. E. Rice, T. P. Gujarati, M. Motta, T. Y. Takeshita, E. Lee, J. A. Latone, and J. M. Garcia, “Quantum Computation of Dominant Products in Lithium–Sulfur Batteries,” J. Chem. Phys. 154, 134115 (2021).
- N. S. Blunt, J. Camps, O. Crawford, R. Izsák, S. Leontica, A. Mirani, A. E. Moylett, S. A. Scivier, C. Sünderhauf, P. Schopf, J. M. Taylor, and N. Holzmann, “A Perspective on the Current State-of-the-Art of Quantum Computing for Drug Discovery Applications,” J. Chem. Theory Comput. 18(12), 7001–7023 (2022a).
- V. von Burg, G. H. Low, T. Häner, D. S. Steiger, M. Reiher, M. Roetteler, and M. Troyer, “Quantum Computing Enhanced Computational Catalysis,” Phys. Rev. Research 3, 033055 (2021).
- A. Aspuru-Guzik, A. D. Dutoi, P. J. Love, and M. Head-Gordon, “Simulated Quantum Computation of Molecular Energies,” Science 309, 1704–1707 (2005).
- B. P. Lanyon, J. D. Whitfield, G. G. Gillett, M. E. Goggin, M. P. Almeida, I. Kassal, J. D. Biamonte, M. Mohseni, B. J. Powell, M. Barbieri, A. Aspuru-Guzik, and A. G. White, “Towards Quantum Chemistry on a Quantum Computer,” Nat. Chem. 2, 106–111 (2010).
- G. H. Low and I. L. Chuang, “Hamiltonian Simulation by Qubitization,” Quantum 3, 163 (2019).
- R. Babbush, C. Gidney, D. W. Berry, N. Wiebe, J. McClean, A. Paler, A. Fowler, and H. Neven, “Encoding Electronic Spectra in Quantum Circuits with Linear T Complexity,” Phys. Rev. X 8, 041015 (2018).
- J. Lee, D. W. Berry, C. Gidney, W. J. Huggins, J. R. McClean, N. Wiebe, and R. Babbush, “Even More Efficient Quantum Computations of Chemistry Through Tensor Hypercontraction,” PRX Quantum 2, 030305 (2021).
- M. Reiher, N. Wiebe, K. M. Svore, D. Wecker, and M. Troyer, “Elucidating Reaction Mechanisms on Quantum Computers,” Proc. Natl. Acad. Sci. U.S.A. 114, 7555–7560 (2017).
- N. S. Blunt, J. Camps, O. Crawford, R. Izsák, S. Leontica, A. Mirani, A. E. Moylett, S. A. Scivier, C. Sünderhauf, P. Schopf, J. M. Taylor, and N. Holzmann, “Perspective on the Current State-of-the-Art of Quantum Computing for Drug Discovery Applications,” J. Chem. Theory Comput. 18, 7001–7023 (2022b).
- J. Preskill, “Quantum Computing in the NISQ era and beyond,” Quantum 2, 79 (2018).
- K. Bharti, A. Cervera-Lierta, T. H. Kyaw, T. Hang, S. Alperin-Lea, A. Anand, M. Degroote, H. Heimonen, J. S. Kottmann, T. Menke, W-K. Mok, S. Sim, L-C. Kwek, and A. Aspuru-Guzik, “Noisy Intermediate-Scale Quantum (NISQ) Algorithms,” Rev. Mod. Phys. 94, 015004 (2022).
- A. Peruzzo, J. McClean, P. Shadbolt, M-H. Yung, X-Q. Zhou, P. J. Love, A. Aspuru-Guzik, and J. O’Brien, “A Variational Eigenvalue Solver on a Photonic Quantum Processor,” Nat. Commun. 5, 5213 (2014).
- P. J. J. O’Malley, R. Babbush, I. D. Kivlichan, J. Romero, J. R. McClean, and et al, “Scalable Quantum Simulation of Molecular Energies,” Phys. Rev. X 6, 031007 (2016).
- A. Kandala, A. Mezzacapo, K. Temme, M. Takita, M. Brink, J. M. Chow, and J. M. Gambetta, “Hardware-Efficient Variational Quantum Eigensolver for Small Molecules and Quantum Magnets,” Nature 549, 242–246 (2017).
- Google AI Quantum and Collaborators, “Hartree-Fock on a Superconducting Qubit Quantum Computer,” Science 369, 1084–1089 (2020).
- Y. Nam, J-S. Chen, N. C. Pisenti, K. Wright, C. Delaney, D. Maslov, K. R. Brown, S. Allen, J. M. Amini, J. Apisdorf, K. M. Beck, A. Blinov, V. Chaplin, M. Chmielewski, C. Collins, S. Debnath, K. M. Hudek, A. M. Ducore, M. Keesan, S. M. Kreikemeier, J. Mizrahi, P. Solomon, M. Williams, J. D. Wong-Campos, D. Moehring, C. Monroe, and J. Kim, “Ground-State Energy Estimation of the Water Molecule on a Trapped-Ion Quantum Computer,” npj Quantum Information 6, 33 (2020).
- Q. Wang, M. Li, C. Monroe, and Y. Nam, “Resource-Optimized Fermionic Local-Hamiltonian Simulation on a Quantum Computer for Quantum Chemistry,” Preprint at https://doi.org/10.22331/q-2021-07-26-509 (2021).
- H. R. Grimsley, D. Claudino, S. E. Economou, E. Barnes, and N. J. Mayhall, “Is the Trotterized UCCSD Ansatz Chemically Well-Defined?” J. Chem. Theory Comput. 16, 1–6 (2020).
- H. R. Grimsley, S. E. Economou, E. Barnes, and N. J. Mayhall, “An Adaptive Variational Algorithm for Exact Molecular Simulations on a Quantum Computer,” Nat. Commun. 10, 3007 (2019).
- A. J. McCaskey, Z. P. Parks, J. Jakowski, S. V. Moore, T. D. Morris, T. S. Humble, and R. C. Pooser, “Quantum Chemistry as a Benchmark for Near-Term Quantum Computers,” npj Quantum Information 5, 99 (2019).
- L. Zhao, J. Goings, K. Wright, J. Nguyen, J. Kim, S. Johri, K. Shin, W. Kyoung, J. I. Fuks, J-K. K. Rhee, and Y. M. Rhee, “Orbital-Optimized Pair-Correlated Electron Simulations on Trapped-Ion Quantum Computers,” npj Quantum Information 9 (2023).
- I. O. Sokolov, P. KI. Barkoutsos, P. J. Ollitrault, D. Greenberg, J. Rice, M. Pistoia, and I. Tavernelli, “Quantum Orbital-Optimized Unitary Coupled Cluster Methods in the Strongly Correlated Regime: Can Quantum Algorithms Outperform Their Classical Equivalents?” J. Chem. Phys. 152, 124107 (2020).
- T. E. O’Brien and et al, “Purification-based Quantum Error Mitigation of Pair-Correlated Electron Simulations,” Nat. Phys. (2023).
- L. Zhao and E. Neuscamman, “Amplitude Determinant Coupled Cluster with Pairwise Doubles,” J. Chem. Theory Comput. 12, 5841–5850 (2016).
- J. Goings, L. Zhao, J. Jakowski, T. Morris, and R. Pooser, “Molecular Symmetry in VQE: A Dual Approach for Trapped-Ion Simulations of Benzene,” Preprint at https://doi.org/10.48550/arXiv.2308.00667 (2023).
- P. A. Limacher, T. D. Kim, P. W. Ayers, P. A. Johnson, S. D. Baerdemacker, D. Van Neck, and P. Bultinck, “The Influence of Orbital Rotation on the Energy of Closed-Shell Wavefunctions,” Mol. Phys. 112, 853–862 (2014).
- T. M. Henderson, I. W. Bulik, and G. E. Scuseria, “Pair Extended Coupled Cluster Doubles,” J. Chem. Phys. 142, 214116 (2015).
- P. Gokhale, O. Angiuli, Y. Ding, K. Gui, T. Tomesh, M. Suchara, M. Martonosi, and F. T. Chong, “Minimizing State Preparations in Variational Quantum Eigensolver by Partitioning into Commuting Families,” arXiv preprint, arXiv:1907.13623v1 (2019).
- “Regularized Orbtital-Optimized Second-Order Møller-Plesset Perturbation Theory: A Reliable Fifth-Order-Scaling Electron Correlation Model with Orbital Energy Dependent Regularizers,” J. Chem. Theory Comput. 14(10), 5203–5219 (2018).
- ‘‘Regularized Second-Order Møller–Plesset Theory: A More Accurate Alternative to Conventional MP2 for Noncovalent Interactions and Transition Metal Thermochemistry for the Same Computational Cost,” J. Chem. Theory Comput. 12(50), 12084–12097 (2021).
- Qiskit contributors, “Qiskit: An Open-Source Framework for Quantum Computing,” (2023).
- Qiming Sun, Timothy C. Berkelbach, Nick S. Blunt, George H. Booth, Sheng Guo, Zhendong Li, Junzi Liu, James D. McClain, Elvira R. Sayfutyarova, Sandeep Sharma, Sebastian Wouters, and Garnet Kin Lic Chan, “PySCF: the Python-Based Simulations of Chemistry Framework,” Wiley Interdiscip. Rev. Comput. Mol. Sci. 8 (2018).
- Y. M. Rhee and M. S. Kim, “Dynamic Isotope Effect on the Product Energy Partitioning in CH22{}_{2}start_FLOATSUBSCRIPT 2 end_FLOATSUBSCRIPTOH→→{}^{\rightarrow}start_FLOATSUPERSCRIPT → end_FLOATSUPERSCRIPTCHO+{}^{+}start_FLOATSUPERSCRIPT + end_FLOATSUPERSCRIPT+H22{}_{2}start_FLOATSUBSCRIPT 2 end_FLOATSUBSCRIPT ,” J. Chem. Phys. 109, 5363 (1998).
- G. Henkelman, B. P. Uberuaga, and H. Jónsson, “A Climbing Image Nudged Elastic Band Method for Finding Saddle Points and Minimum Energy Paths,” J. Chem. Phys. 113, 9901–9904 (2000).
- G. Henkelman and H. Jónsson, “Improved Tangent Estimate in the Nudged Elastic Band Method for Finding Minimum Energy Paths and Saddle Points,” J. Chem. Phys. 113, 9978–9985 (2000).
- D. Sheppard, R. Terrell, and G. Henkelman, “Optimization Methods for Finding Minimum Energy Paths,” J. Chem. Phys. 128, 134106 (2008).
- J-S. Chen, E. Nielsen, M. Ebert, V. Inlek, K. Wright, V. Chaplin, A. Maksymov, E. Páez, A. Poudel, P. Maunz, and J. Gamble, “Benchmarking a Trapped-Ion Quantum Computer with 29 Algorithmic Qubits,” Preprint at https://doi.org/10.48550/arXiv.2308.05071 (2023).
- P. Kl. Barkoutsos, J. F. Gonthier, I. Sokolov, N. Moll, G. Salis, A. Fuhrer, M. Ganzhorn, D. J. Egger, M. Troyer, A. Mezzacapo, S. Filipp, and I. Tavernelli, “Quantum Algorithms for Electronic Structure Calculations: Particle-Hole Hamiltonian and Optimized Wave-Function Expansions,” Phys. Rev. A 98, 022322 (2018).
- I. G. Ryabinkin, T-C. Yen, S. N. Genin, and A. F. Izmaylov, “Qubit Coupled Cluster Method: A Systematic Approach to Quantum Chemistry on a Quantum Computer,” J. Chem. Theory Comput. 14, 6317–6326 (2018).
- I. G. Ryabinkin, R. A. Lang, S. N. Genin, and A. F. Izmaylov, “Iterative Qubit Coupled Cluster Approach with Efficient Screening of Generators,” J. Chem. Theory Comput. 16, 1055–1063 (2020).
- G-L. R. Anselmetti, D. Wierichs, C. Gogolin, and R. M. Parrish, “Local, Expressive, Quantum-Number-Preserving VQE ansätze for Fermionic Systems,” New J. Phys. 23, 113010 (2021).
- U. Baek, D. Hait, J. Shee, O. Leimkuhler, W. J. Huggins, T. F. Stetina, M. Head-Gordon, and K. B. Whaley, “Say NO to Optimization: A Nonorthogonal Quantum Eigensolver,” PRX Quantum 4, 030307 (2023).