Scalable High-Performance Fluxonium Quantum Processor

Abstract

The technological development of hardware heading toward universal fault-tolerant quantum computation requires a large-scale processing unit with high performance. While fluxonium qubits are promising with high coherence and large anharmonicity, their scalability has not been systematically explored. In this work, we propose a superconducting quantum information processor based on compact high-coherence fluxoniums with suppressed crosstalk, reduced design complexity, improved operational efficiency, high-fidelity gates, and resistance to parameter fluctuations. In this architecture, the qubits are readout dispersively using individual resonators connected to a common bus and manipulated via combined on-chip RF and DC control lines, both of which can be designed to have low crosstalk. A multi-path coupling approach enables exchange interactions between the high-coherence computational states and at the same time suppresses the spurious static ZZ rate, leading to fast and high-fidelity entangling gates. We numerically investigate the cross resonance controlled-NOT and the differential AC-Stark controlled-Z operations, revealing low gate error for qubit-qubit detuning bandwidth of up to 1 GHz. Our study on frequency crowding indicates high fabrication yield for quantum processors consisting of over thousands of qubits. In addition, we estimate low resource overhead to suppress logical error rate using the XZZX surface code. These results promise a scalable quantum architecture with high performance for the pursuit of universal quantum computation.

29 pages, 15 figures

References in corpus (42)

• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
• Charge insensitive qubit design derived from the Cooper pair box
• Surface codes: Towards practical large-scale quantum computation
• QuTiP 2: A Python framework for the dynamics of open quantum systems
• Coupling Superconducting Qubits via a Cavity Bus
• Strong quantum computational advantage using a superconducting quantum processor
• Simple pulses for elimination of leakage in weakly nonlinear qubits
• Quantum information processing with circuit quantum electrodynamics
• Realizing Repeated Quantum Error Correction in a Distance-Three Surface Code
• Approaching Unit Visibility for Control of a Superconducting Qubit with Dispersive Readout
• Superconducting qubit in waveguide cavity with coherence time approaching 0.1ms
• Controlling the spontaneous emission of a superconducting transmon qubit
• AC-Stark Shift and Dephasing of a Superconducting Qubit Strongly Coupled to a Cavity Field
• Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits
• Quantum computing with nearest neighbor interactions and error rates over 1%
• Realization of an Error-Correcting Surface Code with Superconducting Qubits
• Fidelity of quantum operations
• Fast Reset and Suppressing Spontaneous Emission of a Superconducting Qubit
• Analytic control methods for high fidelity unitary operations in a weakly nonlinear oscillator
• Digital quantum simulation of spin models with circuit quantum electrodynamics
• Measurement and Control of Quasiparticle Dynamics in a Superconducting Qubit
• Implementation of low-loss superinductances for quantum circuits
• Process verification of two-qubit quantum gates by randomized benchmarking
• Feedback control of a solid-state qubit using high-fidelity projective measurement
• Initialization by measurement of a two-qubit superconducting circuit
• Microwave-induced coupling of superconducting qubits
• Quasiparticle relaxation of superconducting qubits in the presence of flux
• Fluxonium: an alternative qubit platform for high-fidelity operations
• Suppressing relaxation in superconducting qubits by quasiparticle pumping
• Non-Poissonian Quantum Jumps of a Fluxonium Qubit due to Quasiparticle Excitations
• Machine learning for discriminating quantum measurement trajectories and improving readout
• Operation and intrinsic error budget of a two-qubit cross-resonance gate
• Trapping a single vortex and reducing quasiparticles in a superconducting resonator
• Building Blocks of a Flip-Chip Integrated Superconducting Quantum Processor
• Circuit quantization in the presence of time-dependent external flux
• Simplified Josephson-junction fabrication process for reproducibly high-performance superconducting qubits
• Wirebond crosstalk and cavity modes in large chip mounts for superconducting qubits
• Microwave Package Design for Superconducting Quantum Processors
• Mitigation of Cosmic Ray Effect on Microwave Kinetic Inductance Detector Arrays
• Optimizing frequency allocation for fixed-frequency superconducting quantum processors
• Operating in a deep underground facility improves the locking of gradiometric fluxonium qubits at the sweet spots
• Combining $T_1$ and $T_2$ estimation with randomized benchmarking and bounding the diamond distance

Cited by in corpus (49)

• High-Fidelity, Frequency-Flexible Two-Qubit Fluxonium Gates with a Transmon Coupler
• Observation of Josephson Harmonics in Tunnel Junctions
• Programmable Heisenberg interactions between Floquet qubits
• Optimizing quantum gates towards the scale of logical qubits
• Effects of Laser-Annealing on Fixed-Frequency Superconducting Qubits
• Photon-noise-tolerant dispersive readout of a superconducting qubit using a nonlinear Purcell filter
• Observation of higher-order topological states on a quantum computer
• Fast high-fidelity gates for galvanically-coupled fluxonium qubits using strong flux modulation
• Qudit Dynamical Decoupling on a Superconducting Quantum Processor
• Consistent Quantization of Nearly Singular Superconducting Circuits
• Multi-mode architectures for noise-resilient superconducting qubits
• Fast and Robust Geometric Two-Qubit Gates for Superconducting Qubits and beyond
• A Practical Introduction to Benchmarking and Characterization of Quantum Computers
• Blueprint for all-to-all connected superconducting spin qubits
• CNOT gates for fluxonium qubits via selective darkening of transitions
• Native approach to controlled-Z gates in inductively coupled fluxonium qubits
• High coherence fluxonium manufactured with a wafer-scale uniformity process
• Speeding up qubit control with bipolar single-flux-quantum pulse sequences
• Gatemonium: A Voltage-Tunable Fluxonium
• Measurement-induced state transitions in dispersive qubit readout schemes
• SQ-CARS: A Scalable Quantum Control and Readout System
• Microwave-activated gates between a fluxonium and a transmon qubit
• Hybrid cat-transmon architecture for scalable, hardware-efficient quantum error correction
• Flux-pulse-assisted Readout of a Fluxonium Qubit
• Impact of Josephson junction array modes on fluxonium readout
• Tunneling of fluxons via a Josephson resonant level
• Numerical circuit synthesis and compilation for multi-state preparation
• Sub-Harmonic Control of a Fluxonium Qubit via a Purcell-Protected Flux Line
• Verifying the analogy between transversely coupled spin-1/2 systems and inductively-coupled fluxoniums
• Single-Qubit Gates Beyond the Rotating-Wave Approximation for Strongly Anharmonic Low-Frequency Qubits
• The quartic Blochnium: an anharmonic quasicharge superconducting qubit
• Frozonium: Freezing Anharmonicity in Floquet Superconducting Circuits
• SuperGrad: a differentiable simulator for superconducting processors
• Manipulation of magnetic systems by quantized surface acoustic wave via piezomagnetic effect
• Cross-resonance control of an oscillator with an auxiliary fluxonium qubit
• Viewing protected superconducting qubits through the lens of the cat qubit
• Transmon-assisted high-fidelity controlled-Z gates for integer fluxonium qubits
• Non-demolition fluorescence readout and high-fidelity unconditional reset of a fluxonium qubit via dissipation engineering
• Simultaneous sweet-spot locking of gradiometric fluxonium qubits
• Flux-Trapping Fluxonium Qubit
• High Impedance Granular Aluminum Ring Resonators
• Kicked fluxonium with quantum strange attractor
• Scalable Low-overhead Superconducting Non-local Coupler with Exponentially Enhanced Connectivity
• Microwave-activated high-fidelity three-qubit gate scheme for fixed-frequency superconducting qubits
• Exact amplitudes of parametric processes in driven Josephson circuits
• A fluxonium qubit-based hybrid electromechanical system
• Engineering squeezed thermal reservoirs via passive linear coupling
• Robust multi-mode superconducting circuit optimized for quantum information processing
• Proposal for erasure conversion in integer fluxonium qubits