Demonstrating a long-coherence dual-rail erasure qubit using tunable transmons
Creators: name: Levine, Harry
name: Haim, Arbel
name: Hung, Jimmy S. C.
name: Alidoust, Nasser
name: Kalaee, Mahmoud
name: DeLorenzo, Laura
name: Wollack, E. Alex
name: Arrangoiz-Arriola, Patricio
name: Khalajhedayati, Amirhossein
name: Sanil, Rohan
name: Moradinejad, Hesam
name: Vaknin, Yotam
name: Kubica, Aleksander
name: Hover, David
name: Aghaeimeibodi, Shahriar
name: Alcid, Joshua Ari
name: Baek, Christopher
name: Barnett, James
name: Bawdekar, Kaustubh
name: Bienias, Przemyslaw
name: Carson, Hugh
name: Chen, Cliff
name: Chen, Li
name: Chinkezian, Harut
name: Chisholm, Eric M.
name: Clifford, Andrew
name: Cosmic, R.
name: Crisosto, Nicole
name: Dalzell, Alexander M.
name: Davis, Erik
name: D'Ewart, J. Mitch
name: Diez, Sandra
name: D'Souza, Nathan
name: Dumitrescu, Philipp T.
name: Elkhouly, Essam
name: Fang, Michael
name: Fang, Yawen
name: Flammia, Steven T.
name: Fling, Matthew J.
name: Garcia, Gabriel
name: Gharzai, M. Kabeer
name: Gorshkov, Alexey V.
name: Gray, Mason J.
name: Grimberg, Sebastian
name: Grimsmo, Arne L.
name: Hann, Connor T.
name: He, Yuan
name: Heidel, Steven
name: Howell, Sean
name: Hunt, Matthew
name: Iverson, Joseph K.
name: Jarrige, Ignace
name: Jiang, Liang
name: Jones, William M.
name: Karabalin, Rassul
name: Karalekas, Peter J.
name: Keller, Andrew J.
name: Lasi, Davide
name: Lee, Menyoung
name: Ly, Victor
name: MacCabe, Gregory S.
name: Mahuli, Neha
name: Marcaud, Guillaume
name: Matheny, Matthew H.
name: McArdle, Sam
name: McCabe, Gavin
name: Merton, Gabe
name: Miles, Cody
name: Milsted, Ashley
name: Mishra, Anurag
name: Moncelsi, Lorenzo
name: Naghiloo, Mahdi
name: Noh, Kyungjoo
name: Oblepias, Eric
name: Ortuno, Gerson
name: Owens, John Clai
name: Pagdilao, Jason
name: Panduro, Ashley
name: Paquette, J. -P.
name: Patel, Rishi N.
name: Peairs, Gregory A.
name: Perello, David J.
name: Peterson, Eric C.
name: Ponte, Sophia
name: Putterman, Harald
name: Refael, Gil
name: Reinhold, Philip
name: Resnick, Rachel
name: Reyna, Omar A.
name: Rodriguez, Roberto
name: Rose, Jefferson
name: Rubin, Alex H.
name: Runyan, Marc
name: Ryan, Colm A.
name: Sahmoud, Abdulrahman
name: Scaffidi, Thomas
name: Shah, Bhavik
name: Siavoshi, Salome
name: Sivarajah, Prasahnt
name: Skogland, Trenton
name: Su, Chun-Ju
name: Swenson, Loren J.
name: Sylvia, Jared
name: Teo, Stephanie M.
name: Tomada, Astrid
name: Torlai, Giacomo
name: Wistrom, Mark
name: Zhang, Kailing
name: Zuk, Ido
name: Clerk, Aashish A.
name: Brandão, Fernando G. S. L.
name: Retzker, Alex
name: Painter, Oskar
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Quantum error correction with erasure qubits promises significant advantages over standard error correction due to favorable thresholds for erasure errors. To realize this advantage in practice requires a qubit for which nearly all errors are such erasure errors, and the ability to check for erasure errors without dephasing the qubit. We demonstrate that a "dual-rail qubit" consisting of a pair of resonantly coupled transmons can form a highly coherent erasure qubit, where transmon $T_1$ errors are converted into erasure errors and residual dephasing is strongly suppressed, leading to millisecond-scale coherence within the qubit subspace. We show that single-qubit gates are limited primarily by erasure errors, with erasure probability $p_\text{erasure} = 2.19(2)\times 10^{-3}$ per gate while the residual errors are $\sim 40$ times lower. We further demonstrate mid-circuit detection of erasure errors while introducing $&lt; 0.1\%$ dephasing error per check. Finally, we show that the suppression of transmon noise allows this dual-rail qubit to preserve high coherence over a broad tunable operating range, offering an improved capacity to avoid frequency collisions. This work establishes transmon-based dual-rail qubits as an attractive building block for hardware-efficient quantum error correction.
description: 9+13 pages, 16 figures