Flexible layout of surface code computations using AutoCCZ states
Abstract
We construct a self-correcting CCZ state (the "AutoCCZ") with embedded delayed choice CZs for completing gate teleportations. Using the AutoCCZ state we create efficient surface code spacetime layouts for both a depth-limited circuit (a ripply-carry addition) and a Clifford-limited circuit (a QROM read). Our layouts account for distillation and routing, are based on plausible physical assumptions for a large-scale superconducting qubit platform, and suggest that circuit-level Toffoli parallelism (e.g. using a carry-lookahead adder instead of a ripple-carry adder) will not reduce the execution time of computations involving fewer than five million physical qubits. We reduce the spacetime volume of delayed choice CZs by a factor of 4 compared to techniques from previous work (Fowler 2012), and make several improvements to the CCZ magic state factory from (Gidney 2019).
Cite
@article{arxiv.1905.08916,
title = {Flexible layout of surface code computations using AutoCCZ states},
author = {Craig Gidney and Austin G. Fowler},
journal= {arXiv preprint arXiv:1905.08916},
year = {2019}
}
Comments
16 pages, 18 figures