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Superconducting pairing correlations on a trapped-ion quantum computer
Authors:
Etienne Granet,
Sheng-Hsuan Lin,
Kevin Hémery,
Reza Haghshenas,
Pablo Andres-Martinez,
David T. Stephen,
Anthony Ransford,
Jake Arkinstall,
M. S. Allman,
Pete Campora,
Samuel F. Cooper,
Robert D. Delaney,
Joan M. Dreiling,
Brian Estey,
Caroline Figgatt,
Cameron Foltz,
John P. Gaebler,
Alex Hall,
Ali Husain,
Akhil Isanaka,
Colin J. Kennedy,
Nikhil Kotibhaskar,
Ivaylo S. Madjarov,
Michael Mills,
Alistair R. Milne
, et al. (9 additional authors not shown)
Abstract:
The Fermi-Hubbard model is the starting point for the simulation of many strongly correlated materials, including high-temperature superconductors, whose modelling is a key motivation for the construction of quantum simulation and computing devices. However, the detection of superconducting pairing correlations has so far remained out of reach, both because of their off-diagonal character - which…
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The Fermi-Hubbard model is the starting point for the simulation of many strongly correlated materials, including high-temperature superconductors, whose modelling is a key motivation for the construction of quantum simulation and computing devices. However, the detection of superconducting pairing correlations has so far remained out of reach, both because of their off-diagonal character - which makes them inaccessible to local density measurements - and because of the difficulty of preparing superconducting states. Here, we report measurement of significant pairing correlations in three different regimes of Fermi-Hubbard models simulated on Quantinuum's Helios trapped-ion quantum computer. Specifically, we measure non-equilibrium pairing induced by an electromagnetic field in the half-filled square lattice model, d-wave pairing in an approximate ground state of the checkerboard Hubbard model at $1/6$-doping, and s-wave pairing in a bilayer model relevant to nickelate superconductors. These results show that a quantum computer can reliably create and probe physically relevant states with superconducting pairing correlations, opening a path to the exploration of superconductivity with quantum computers.
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Submitted 17 February, 2026; v1 submitted 3 November, 2025;
originally announced November 2025.
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Digital quantum magnetism on a trapped-ion quantum computer
Authors:
Reza Haghshenas,
Eli Chertkov,
Michael Mills,
Wilhelm Kadow,
Sheng-Hsuan Lin,
Yi-Hsiang Chen,
Chris Cade,
Ido Niesen,
Tomislav Begušić,
Manuel S. Rudolph,
Cristina Cirstoiu,
Kevin Hemery,
Conor Mc Keever,
Michael Lubasch,
Etienne Granet,
Charles H. Baldwin,
John P. Bartolotta,
Matthew Bohn,
Justin J. Burau,
Julia Cline,
Matthew DeCross,
Joan M. Dreiling,
Cameron Foltz,
David Francois,
John P. Gaebler
, et al. (34 additional authors not shown)
Abstract:
Digital quantum matter -- realized when discrete quantum gates approximate continuous time evolution -- is susceptible to heating into chaotic, structureless states. If digitization errors are adequately suppressed, a long-lived transient regime of approximately energy-conserving dynamics can be observed on gate-based quantum computers. Conservation of energy, in turn, enables the exploration of a…
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Digital quantum matter -- realized when discrete quantum gates approximate continuous time evolution -- is susceptible to heating into chaotic, structureless states. If digitization errors are adequately suppressed, a long-lived transient regime of approximately energy-conserving dynamics can be observed on gate-based quantum computers. Conservation of energy, in turn, enables the exploration of a wide variety of complex behaviors observed in equilibrium systems, ranging from the nontrivial microscopic origins of thermalization itself to the stabilization of effective models hosting exotic emergent properties. Here, we use Quantinuum's system model H2 quantum computer to simulate digitized dynamics of the quantum Ising model, suppressing digitization errors well enough to observe thermalization on timescales that severely challenge classical simulation methods. Relaxation of an inhomogeneous state reveals an emergent hydrodynamics due to approximate energy conservation, and we compute the associated diffusion constant. By reprogramming our simulations to take place on a triangular lattice with periodic boundary conditions, we observe thermalization consistent with emergent gauge and topological constraints resulting from lattice frustration. Our results were enabled by continued advances in two-qubit gate quality (native partial entangler fidelities of $99.94(1)\%$), and establish digital quantum computers as powerful tools for studying (effectively) continuous-time dynamics.
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Submitted 21 April, 2026; v1 submitted 26 March, 2025;
originally announced March 2025.
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Qutrit Toric Code and Parafermions in Trapped Ions
Authors:
Mohsin Iqbal,
Anasuya Lyons,
Chiu Fan Bowen Lo,
Nathanan Tantivasadakarn,
Joan Dreiling,
Cameron Foltz,
Thomas M. Gatterman,
Dan Gresh,
Nathan Hewitt,
Craig A. Holliman,
Jacob Johansen,
Brian Neyenhuis,
Yohei Matsuoka,
Michael Mills,
Steven A. Moses,
Peter Siegfried,
Ashvin Vishwanath,
Ruben Verresen,
Henrik Dreyer
Abstract:
The development of programmable quantum devices can be measured by the complexity of manybody states that they are able to prepare. Among the most significant are topologically ordered states of matter, which enable robust quantum information storage and processing. While topological orders are more readily accessible with qudits, experimental realisations have thus far been limited to lattice mod…
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The development of programmable quantum devices can be measured by the complexity of manybody states that they are able to prepare. Among the most significant are topologically ordered states of matter, which enable robust quantum information storage and processing. While topological orders are more readily accessible with qudits, experimental realisations have thus far been limited to lattice models of qubits. Here, we prepare a ground state of the Z3 toric code state on 24 qutrits in a trapped ion quantum processor with fidelity per qutrit exceeding 96.5(3)%. We manipulate two types of defects which go beyond the conventional qubit toric code: a parafermion, and its bound state which is related to charge conjugation symmetry. We further demonstrate defect fusion and the transfer of entanglement between anyons and defects, which we use to control topological qutrits. Our work opens up the space of long-range entangled states with qudit degrees of freedom for use in quantum simulation and universal error-correcting codes.
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Submitted 6 November, 2024;
originally announced November 2024.