Nonplanar qubit with tunable gauge symmetry

• URL: http://arxiv.org/abs/2607.14229v1
• Date: Wed, 15 Jul 2026 18:00:34 GMT
• Title: Nonplanar qubit with tunable gauge symmetry
• Abstract summary: Circuit quantum electrodynamics embeds Josephson junction qubits within superconducting cavities.<n>We show that a non-planar qubit gives rise to flux-tunable $mathbbZ_3$ gauge symmetry.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Circuit quantum electrodynamics embeds Josephson junction qubits within superconducting cavities, and has emerged as a leading approach to quantum computing and quantum simulation. Despite the many permutations of circuit geometry that have been explored, Josephson connectivities have so far been planar, making them effectively low-dimensional. Here we show that a non-planar qubit -- a $3\times3$ crossbar Josephson array -- gives rise to flux-tunable $\mathbb{Z}_3$ combinatorial gauge symmetry (CGS), potentially enabling spin-liquid behavior when networked into a lattice. The observed excitation spectrum shows excellent agreement with predictions from a neural network trained to generate variational quantum states, demonstrating that we have predictive power over our high-dimensional quantum system. Fine-structure splittings near the CGS point are compatible with weak tunneling or symmetry breaking due to experimental imperfections. We additionally use the superconducting cavity to externally induce symmetry breaking, observing a restoration of symmetry at the CGS point where ground states differ only by a $\mathbb{Z}_3$ phase. This work initiates a general program exploring lattice gauge theories using the toolbox of circuit quantum electrodynamics. More broadly, introducing non-planar Josephson connectivities opens a vast space for experimental and theoretical exploration of structures in almost any imaginable dimensionality and geometry.

Related papers

• Localized orbitals and tunnel couplings from general confinement potentials in gate-defined quantum-dot arrays [0.0]
  We present a numerical localization procedure that rotates the eigenbasis of a general one-particle effective orbital Hamiltonian into $s$-, $p$-, $d$-, $ldots$-shells of localized orbital wavefunctions associated with individual quantum dots.<n>We demonstrate this procedure on a 2D triangular Si-MOS triple-quantum-dot array by obtaining the voltage dependencies of the tunnel couplings and their distributions in the presence of disorder.
  arXiv  Detail & Related papers  (2026-08-30T12:52:50Z)
• Symmetry-protected topology and deconfined solitons in a multi-link $\mathbb{Z}_2$ gauge theory [45.88028371034407]
  We study a $mathbbZ$ lattice gauge theory defined on a multi-graph with links that can be visualized as great circles of a spherical shell.<n>We show that this leads to state-dependent tunneling amplitudes underlying a phenomenon analogous to the Peierls instability.<n>By performining a detailed analysis based on matrix product states, we prove that charge deconfinement emerges as a consequence of charge-fractionalization.
  arXiv  Detail & Related papers  (2026-03-02T22:59:25Z)
• Quantum model for black holes and clocks [41.99844472131922]
  We consider a stationary quantum system consisting of two non-interacting yet entangled subsystems, $$ and $$.<n>We identify a quantum theory characterizing $$ such that, in the quantum-to-classical crossover of the composite system, $$ behaves as a test particle within the gravitational field of a Schwarzschild Black Hole.<n>This leads us to discuss how the quantum model for $$ endows the SBH with all the characteristics of a "perfect" clock.
  arXiv  Detail & Related papers  (2026-01-12T11:26:06Z)
• Quantum sensor network metrology with bright solitons [39.58317527488534]
  General Heisenberg Limit (GHL) characterizes fundamental limitations for unknown parameter measurement and estimation accuracy.<n>Three-mode soliton Josephson junction (TMSJJ) system as a three mode extension for the soliton Josephson junction (SJJ) bosonic model.<n>Our findings open new prospects for quantum network sensorics with atomtronic circuits.
  arXiv  Detail & Related papers  (2025-07-21T08:01:36Z)
• Meson spectroscopy of exotic symmetries of Ising criticality in Rydberg atom arrays [39.58317527488534]
  Coupling two Ising chains in a ladder leads to an even richer $mathcalD(1)_8$ symmetries.<n>Here, we probe these emergent symmetries in a Rydberg atom processing unit, leveraging its geometry to realize both chain and ladder configurations.
  arXiv  Detail & Related papers  (2025-06-26T14:19:30Z)
• Spontaneous symmetry breaking in a $SO(3)$ non-Abelian lattice gauge theory in $2+1$D with quantum algorithms [0.0]
  We study the ability of quantum algorithms to prepare ground states in a matter-free non-Abelian $SO(3)$ lattice gauge theory in $2+1$D.<n>To deal with the large Hilbert space of gauge fields, we demonstrate how the exact imposition of the non-Abelian Gauss Law in the rishon representation of the quantum link operator significantly reduces the degrees of freedom.
  arXiv  Detail & Related papers  (2024-09-11T08:55:59Z)
• Topological Josephson Junctions in the Integer Quantum Hall Regime [42.408991654684876]
  tunable Josephson junctions (TJJs) are desirable platforms for investigating the anomalous Josephson effect and topological quantum insulator applications. We propose a robust and electrostatically tunable TJJ by combining the physics of the integer quantum Hall (IQH) regime and of superconductors. They are of particular relevance towards scalable and robust Andreev-qubit platforms, and also for efficient phase batteries.
  arXiv  Detail & Related papers  (2022-11-04T16:45:07Z)
• Tuning the Topological $\theta$-Angle in Cold-Atom Quantum Simulators of Gauge Theories [3.4075669047370125]
  We show how a tunable topological $theta$-term can be added to a prototype theory with gauge symmetry. The model can be realized experimentally in a single-species Bose--Hubbard model in an optical superlattice with three different spatial periods. This work opens the door towards studying the rich physics of topological gauge-theory terms in large-scale cold-atom quantum simulators.
  arXiv  Detail & Related papers  (2022-04-13T18:00:01Z)
• Photon-mediated Stroboscopic Quantum Simulation of a $\mathbb{Z}_{2}$ Lattice Gauge Theory [58.720142291102135]
  Quantum simulation of lattice gauge theories (LGTs) aims at tackling non-perturbative particle and condensed matter physics. One of the current challenges is to go beyond 1+1 dimensions, where four-body (plaquette) interactions, not contained naturally in quantum simulating devices, appear. We show how to prepare the ground state and measure Wilson loops using state-of-the-art techniques in atomic physics.
  arXiv  Detail & Related papers  (2021-07-27T18:10:08Z)
• $\mathbb{Z}_3$ quantum double in a superconducting wire array [1.3159512679346685]
  We show that a quantum double can be realized in an array of superconducting wires coupled via Josephson junctions. Our model maps to a quantum three-state Potts model under a duality transformation.
  arXiv  Detail & Related papers  (2021-01-05T19:00:00Z)
• Emergent $\mathcal{PT}$ symmetry in a double-quantum-dot circuit QED set-up [0.0]
  We show that a non-Hermitian Hamiltonian emerges naturally in a double-quantum-dot-circuit-QED set-up. Our results pave the way for an on-chip realization of a potentially scalable non-Hermitian system.
  arXiv  Detail & Related papers  (2020-04-16T09:08:31Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.