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arXiv · 2511.05465

Helios: A 98-qubit trapped-ion quantum computer

Anthony Ransford·M. S. Allman·Jake Arkinstall·J. P. Campora III·Samuel F. Cooper·Robert D. Delaney·Joan M. Dreiling·Brian Estey·Caroline Figgatt·Alex Hall·Ali A. Husain·Akhil Isanaka·Colin J. Kennedy·Nikhil Kotibhaskar·Ivaylo S. Madjarov·Karl Mayer·Alistair R. Milne·Annie J. Park·Adam P. Reed·Riley Ancona·Molly P. Andersen·Pablo Andres-Martinez·Will Angenent·Liz Argueta·Benjamin Arkin·Leonardo Ascarrunz·William Baker·Corey Barnes·John Bartolotta·Jordan Berg·Ryan Besand·Bryce Bjork·Matt Blain·Paul Blanchard·Robin Blume-Kohout·Matt Bohn·Agustin Borgna·Daniel Y. Botamanenko·Robert Boutelle·Natalie Brown·Grant T. Buckingham·Nathaniel Q. Burdick·William Cody Burton·Varis Carey·Christopher J. Carron·Joe Chambers·John Children·Victor E. Colussi·Steven Crepinsek·Andrew Cureton·Joe Davies·Daniel Davis·Matthew DeCross·David Deen·Conor Delaney·Davide DelVento·B. J. DeSalvo·Jason Dominy·Ross Duncan·Vanya Eccles·Alec Edgington·Neal Erickson·Stephen Erickson·Christopher T. Ertsgaard·Bruce Evans·Tyler Evans·Maya I. Fabrikant·Andrew Fischer·Cameron Foltz·Michael Foss-Feig·David Francois·Brad Freyberg·Charles Gao·Robert Garay·Jane Garvin·David M. Gaudiosi·Christopher N. Gilbreth·Josh Giles·Erin Glynn·Jeff Graves·Azure Hansen·David Hayes·Lukas Heidemann·Bob Higashi·Tyler Hilbun·Jordan Hines·Ariana Hlavaty·Kyle Hoffman·Ian M. Hoffman·Craig Holliman·Isobel Hooper·Bob Horning·James Hostetter·Daniel Hothem·Jack Houlton·Jared Hout·Ross Hutson·Ryan T. Jacobs·Trent Jacobs·Melf Johannsen

Abstract

We report on Quantinuum Helios, a 98-qubit trapped-ion quantum processor based on the quantum charge-coupled device (QCCD) architecture. Helios features $^{137}$Ba$^{+}$ hyperfine qubits, all-to-all connectivity enabled by a rotatable ion storage ring connecting two quantum operation regions by a junction, speed improvements from parallelized operations, and a new software stack with real-time compilation of dynamic programs. Averaged over all operational zones in the system, we achieve average infidelities of $2.5(1)\times10^{-5}$ for single-qubit gates, $7.9(2)\times10^{-4}$ for two-qubit gates, and $4.8(6)\times10^{-4}$ for state preparation and measurement, none of which are fundamentally limited and likely able to be improved. These component infidelities are predictive of system-level performance in both random Clifford circuits and random circuit sampling, the latter demonstrating that Helios operates well beyond the reach of classical simulation and establishes a new frontier of fidelity and complexity for quantum computers.

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Anthony Ransford, M. S. Allman, Jake Arkinstall, J. P. Campora III, Samuel F. Cooper, Robert D. Delaney, Joan M. Dreiling, Brian Estey, Caroline Figgatt, Alex Hall, Ali A. Husain, Akhil Isanaka, Colin J. Kennedy, Nikhil Kotibhaskar, Ivaylo S. Madjarov, Karl Mayer, Alistair R. Milne, Annie J. Park, Adam P. Reed, Riley Ancona, Molly P. Andersen, Pablo Andres-Martinez, Will Angenent, Liz Argueta, Benjamin Arkin, Leonardo Ascarrunz, William Baker, Corey Barnes, John Bartolotta, Jordan Berg, Ryan Besand, Bryce Bjork, Matt Blain, Paul Blanchard, Robin Blume-Kohout, Matt Bohn, Agustin Borgna, Daniel Y. Botamanenko, Robert Boutelle, Natalie Brown, Grant T. Buckingham, Nathaniel Q. Burdick, William Cody Burton, Varis Carey, Christopher J. Carron, Joe Chambers, John Children, Victor E. Colussi, Steven Crepinsek, Andrew Cureton, Joe Davies, Daniel Davis, Matthew DeCross, David Deen, Conor Delaney, Davide DelVento, B. J. DeSalvo, Jason Dominy, Ross Duncan, Vanya Eccles, Alec Edgington, Neal Erickson, Stephen Erickson, Christopher T. Ertsgaard, Bruce Evans, Tyler Evans, Maya I. Fabrikant, Andrew Fischer, Cameron Foltz, Michael Foss-Feig, David Francois, Brad Freyberg, Charles Gao, Robert Garay, Jane Garvin, David M. Gaudiosi, Christopher N. Gilbreth, Josh Giles, Erin Glynn, Jeff Graves, Azure Hansen, David Hayes, Lukas Heidemann, Bob Higashi, Tyler Hilbun, Jordan Hines, Ariana Hlavaty, Kyle Hoffman, Ian M. Hoffman, Craig Holliman, Isobel Hooper, Bob Horning, James Hostetter, Daniel Hothem, Jack Houlton, Jared Hout, Ross Hutson, Ryan T. Jacobs, Trent Jacobs, Melf Johannsen. 2025-11-07. Helios: A 98-qubit trapped-ion quantum computer. https://arxiv.org/abs/2511.05465

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