Paper

Purification-based quantum error mitigation of pair-correlated electron simulations

Newman, M, Miao, K C, Campero, J, Montazeri, S, Kieferová, M, Bengtsson, A, Xing, C, Shutty, N, Lester, B J, Nguyen, A, Lill, A T, Khezri, M, Bortoli, G, Bourassa, A, Opremcak, A, Nguyen, M, Rocque, C, Lucero, E, Potter, R, Jiang, Z, Bacon, D, Anselmetti, G, Polla, S, Laws, L, Rubin, N C, Crook, A L, Mieszala, A, Thor, D, Sankaragomathi, K, Boixo, S, Burger, T, Isakov, S V, Conner, P, Faoro, L, L Flores Burgos, Quintana, C, Chik, D, Movassagh, R, Demura, S, Klots, A R, Kothari, R, Yao, Z J, Laptev, P, Liu, W, Mohseni, M, Mandra, S, Arya, K, Torres, A, Gidney, C, Habegger, S, Locharla, A, Hansen, M, Gosula, R, Villalonga, B, Bushnell, N, Schurkus, H F, Smith, W C, Hong, S, Farhi, E, Korotkov, A N, Foxen, B, Young, G, Harrington, S D, Neill, C, Zalcman, A, Fowler, A G, C Vollgraff Heidweiller, Kechedzhi, K, Neven, H, Saei, N, Erickson, C, Chiaro, B, O'Brien, T E, Malone, F D, Zhang, Y, Anderson, K, Babbush, R, Allen, R, Giang, W, Curtin, B, Kostritsa, F, Dau, A Grajales, Khattar, T, Somma, R, White, T, Pryadko, L P, Cogan, J, McEwen, M, Kreikebaum, J M, Lee, J, Lee, K, Satzinger, K J, Aleiner, I, McClean, J R, Elfving, V E, Zhu, N, Shearn, M J, Yoo, J, Arute, F, Megrant, A

2022

Overview

An important measure of the development of quantum computing platforms has been the simulation of increasingly complex physical systems. Prior to fault-tolerant quantum computing, robust error mitigation strategies are necessary to continue this growth. Here, we study physical simulation within the seniority-zero electron pairing subspace, which affords both a computational stepping stone to a fully correlated model, and an opportunity to validate recently introduced ``purification-based'' error-mitigation strategies. We compare the performance of error mitigation based on doubling quantum resources in time (echo verification) or in space (virtual distillation), on up to \\(20\\) qubits of a superconducting qubit quantum processor. We observe a reduction of error by one to two orders of magnitude below less sophisticated techniques (e.g. post-selection); the gain from error mitigation is seen to increase with the system size. Employing these error mitigation strategies enables the implementation of the largest variational algorithm for a correlated chemistry system to-date. Extrapolating performance from these results allows us to estimate minimum requirements for a beyond-classical simulation of electronic structure. We find that, despite the impressive gains from purification-based error mitigation, significant hardware improvements will be required for classically intractable variational chemistry simulations.

• Publisher: Cornell University Library, arXiv.org
• Subject: Algorithms / Distillation / Electronic structure / Error reduction / Fault tolerance / Microprocessors / Physical simulation / Purification / Quantum computing / Qubits (quantum computing) / Simulation