Implementation of pairwise longitudinal coupling in a three-qubit superconducting circuit

Abstract

We present the "trimon", a multi-mode superconducting circuit implementing three qubits with all-to-all longitudinal coupling. This always-on interaction enables simple implementation of generalized controlled-NOT gates which form a universal set. Further, two of the three qubits are protected against Purcell decay while retaining measurability. We demonstrate high-fidelity state swapping operations between two qubits and characterize the coupling of all three qubits to a neighbouring transmon qubit. Our results offer a new paradigm for multi-qubit architecture with applications in quantum error correction, quantum simulations and quantum annealing.

Main text (5 pages, 4 figures) and Supplementary Material (11 pages, 5 figures)

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Cited by in corpus (26)

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• Scalable and Robust Photonic Integrated Unitary Converter
• QuCAT: Quantum Circuit Analyzer Tool in Python
• Engineering Purely Nonlinear Coupling with the Quarton
• Fast multiplexed superconducting qubit readout with intrinsic Purcell filtering
• Benchmarking the readout of a superconducting qubit for repeated measurements
• Native three-body interaction in superconducting circuits
• Polariton spectrum of the Dicke-Ising model
• Lattice gauge theory and dynamical quantum phase transitions using noisy intermediate scale quantum devices
• Multi-mode superconducting circuits for realizing strongly coupled multi-qubit processor units
• Kinetic Inductance Parametric Converter
• Engineering Cross Resonance Interaction in Multi-modal Quantum Circuits
• Qubit readouts enabled by qubit cloaking
• Efficient decoupling of a non-linear qubit mode from its environment
• Three-qubit direct dispersive parity measurement with Tunable Coupling Qubits
• Near-ultrastrong nonlinear light-matter coupling in superconducting circuits
• Suppressed crosstalk between two-junction superconducting qubits with mode-selective exchange coupling
• Lattice Hamiltonians and Stray Interactions Within Quantum Processors
• Transmon-qubit readout using in-situ bifurcation amplification in the mesoscopic regime
• Algorithmic Primitives for Quantum-Assisted Quantum Control
• Spectrum analysis with parametrically modulated transmon qubits
• Characterisation of spatial charge sensitivity in a multi-mode superconducting qubit
• Hierarchies among genuine multipartite entangling capabilities of quantum gates