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arXiv · 2412.14360

Demonstrating dynamic surface codes

Alec Eickbusch·Matt McEwen·Volodymyr Sivak·Alexandre Bourassa·Juan Atalaya·Jahan Claes·Dvir Kafri·Craig Gidney·Christopher W. Warren·Jonathan Gross·Alex Opremcak·Nicholas Zobrist·Kevin C. Miao·Gabrielle Roberts·Kevin J. Satzinger·Andreas Bengtsson·Matthew Neeley·William P. Livingston·Alex Greene·Rajeev Acharya·Laleh Aghababaie Beni·Georg Aigeldinger·Ross Alcaraz·Trond I. Andersen·Markus Ansmann·Frank Arute·Kunal Arya·Abraham Asfaw·Ryan Babbush·Brian Ballard·Joseph C. Bardin·Alexander Bilmes·Jenna Bovaird·Dylan Bowers·Leon Brill·Michael Broughton·David A. Browne·Brett Buchea·Bob B. Buckley·Tim Burger·Brian Burkett·Nicholas Bushnell·Anthony Cabrera·Juan Campero·Hung-Shen Chang·Ben Chiaro·Liang-Ying Chih·Agnetta Y. Cleland·Josh Cogan·Roberto Collins·Paul Conner·William Courtney·Alexander L. Crook·Ben Curtin·Sayan Das·Alexander Del Toro Barba·Sean Demura·Laura De Lorenzo·Agustin Di Paolo·Paul Donohoe·Ilya K. Drozdov·Andrew Dunsworth·Aviv Moshe Elbag·Mahmoud Elzouka·Catherine Erickson·Vinicius S. Ferreira·Leslie Flores Burgos·Ebrahim Forati·Austin G. Fowler·Brooks Foxen·Suhas Ganjam·Gonzalo Garcia·Robert Gasca·Élie Genois·William Giang·Dar Gilboa·Raja Gosula·Alejandro Grajales Dau·Dietrich Graumann·Tan Ha·Steve Habegger·Michael C. Hamilton·Monica Hansen·Matthew P. Harrigan·Sean D. Harrington·Stephen Heslin·Paula Heu·Oscar Higgott·Reno Hiltermann·Jeremy Hilton·Hsin-Yuan Huang·Ashley Huff·William J. Huggins·Evan Jeffrey·Zhang Jiang·Xiaoxuan Jin·Cody Jones·Chaitali Joshi·Pavol Juhas·Andreas Kabel

Abstract

A remarkable characteristic of quantum computing is the potential for reliable computation despite faulty qubits. This can be achieved through quantum error correction, which is typically implemented by repeatedly applying static syndrome checks, permitting correction of logical information. Recently, the development of time-dynamic approaches to error correction has uncovered new codes and new code implementations. In this work, we experimentally demonstrate three time-dynamic implementations of the surface code, each offering a unique solution to hardware design challenges and introducing flexibility in surface code realization. First, we embed the surface code on a hexagonal lattice, reducing the necessary couplings per qubit from four to three. Second, we walk a surface code, swapping the role of data and measure qubits each round, achieving error correction with built-in removal of accumulated non-computational errors. Finally, we realize the surface code using iSWAP gates instead of the traditional CNOT, extending the set of viable gates for error correction without additional overhead. We measure the error suppression factor when scaling from distance-3 to distance-5 codes of $\Lambda_{35,\text{hex}} = 2.15(2)$, $\Lambda_{35,\text{walk}} = 1.69(6)$, and $\Lambda_{35,\text{iSWAP}} = 1.56(2)$, achieving state-of-the-art error suppression for each. With detailed error budgeting, we explore their performance trade-offs and implications for hardware design. This work demonstrates that dynamic circuit approaches satisfy the demands for fault-tolerance and opens new alternative avenues for scalable hardware design.

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Alec Eickbusch, Matt McEwen, Volodymyr Sivak, Alexandre Bourassa, Juan Atalaya, Jahan Claes, Dvir Kafri, Craig Gidney, Christopher W. Warren, Jonathan Gross, Alex Opremcak, Nicholas Zobrist, Kevin C. Miao, Gabrielle Roberts, Kevin J. Satzinger, Andreas Bengtsson, Matthew Neeley, William P. Livingston, Alex Greene, Rajeev Acharya, Laleh Aghababaie Beni, Georg Aigeldinger, Ross Alcaraz, Trond I. Andersen, Markus Ansmann, Frank Arute, Kunal Arya, Abraham Asfaw, Ryan Babbush, Brian Ballard, Joseph C. Bardin, Alexander Bilmes, Jenna Bovaird, Dylan Bowers, Leon Brill, Michael Broughton, David A. Browne, Brett Buchea, Bob B. Buckley, Tim Burger, Brian Burkett, Nicholas Bushnell, Anthony Cabrera, Juan Campero, Hung-Shen Chang, Ben Chiaro, Liang-Ying Chih, Agnetta Y. Cleland, Josh Cogan, Roberto Collins, Paul Conner, William Courtney, Alexander L. Crook, Ben Curtin, Sayan Das, Alexander Del Toro Barba, Sean Demura, Laura De Lorenzo, Agustin Di Paolo, Paul Donohoe, Ilya K. Drozdov, Andrew Dunsworth, Aviv Moshe Elbag, Mahmoud Elzouka, Catherine Erickson, Vinicius S. Ferreira, Leslie Flores Burgos, Ebrahim Forati, Austin G. Fowler, Brooks Foxen, Suhas Ganjam, Gonzalo Garcia, Robert Gasca, Élie Genois, William Giang, Dar Gilboa, Raja Gosula, Alejandro Grajales Dau, Dietrich Graumann, Tan Ha, Steve Habegger, Michael C. Hamilton, Monica Hansen, Matthew P. Harrigan, Sean D. Harrington, Stephen Heslin, Paula Heu, Oscar Higgott, Reno Hiltermann, Jeremy Hilton, Hsin-Yuan Huang, Ashley Huff, William J. Huggins, Evan Jeffrey, Zhang Jiang, Xiaoxuan Jin, Cody Jones, Chaitali Joshi, Pavol Juhas, Andreas Kabel. 2024-12-18. Demonstrating dynamic surface codes. https://arxiv.org/abs/2412.14360

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