Enhancing Dispersive Readout of Superconducting Qubits Through Dynamic Control of the Dispersive Shift: Experiment and Theory

Abstract

The performance of a wide range of quantum computing algorithms and protocols depends critically on the fidelity and speed of the employed qubit readout. Examples include gate sequences benefiting from mid-circuit, real-time, measurement-based feedback, such as qubit initialization, entanglement generation, teleportation, and perhaps most importantly, quantum error correction. A prominent and widely-used readout approach is based on the dispersive interaction of a superconducting qubit strongly coupled to a large-bandwidth readout resonator, frequently combined with a dedicated or shared Purcell filter protecting qubits from decay. By dynamically reducing the qubit-resonator detuning and thus increasing the dispersive shift, we demonstrate a beyond-state-of-the-art two-state-readout error of only $0.25\%$ in 100 ns integration time. Maintaining low readout-drive strength, we nearly quadruple the signal-to-noise ratio of the readout by doubling the readout mode linewidth, which we quantify by considering the hybridization of the readout-resonator and its dedicated Purcell-filter. We find excellent agreement between our experimental data and our theoretical model. The presented results are expected to further boost the performance of new and existing algorithms and protocols critically depending on high-fidelity, fast, mid-circuit measurements.

References in corpus (52)

• Fault-tolerant quantum computation by anyons
• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
• Charge insensitive qubit design derived from the Cooper pair box
• Concentrating Partial Entanglement by Local Operations
• Cavity quantum electrodynamics for superconducting electrical circuits: an architecture for quantum computation
• Circuit Quantum Electrodynamics
• Quantum Teleportation is a Universal Computational Primitive
• Universal Quantum Computation with ideal Clifford gates and noisy ancillas
• Suppressing quantum errors by scaling a surface code logical qubit
• Approaching Unit Visibility for Control of a Superconducting Qubit with Dispersive Readout
• Preparation and Measurement of Three-Qubit Entanglement in a Superconducting Circuit
• AC-Stark Shift and Dephasing of a Superconducting Qubit Strongly Coupled to a Cavity Field
• Fast Scalable State Measurement with Superconducting Qubits
• Exponential suppression of bit or phase flip errors with repetitive error correction
• Repeated Quantum Error Detection in a Surface Code
• Realizing Rapid, High-Fidelity, Single-Shot Dispersive Readout of Superconducting Qubits
• To catch and reverse a quantum jump mid-flight
• Realization of Deterministic Quantum Teleportation with Solid State Qubits
• Single-shot qubit readout in circuit Quantum Electrodynamics
• Single-shot qubit readout in circuit Quantum Electrodynamics
• High-Fidelity Readout in Circuit Quantum Electrodynamics Using the Jaynes-Cummings Nonlinearity
• Fast Reset and Suppressing Spontaneous Emission of a Superconducting Qubit
• Rapid high-fidelity multiplexed readout of superconducting qubits
• Digital quantum simulation of spin models with circuit quantum electrodynamics
• Fast and Unconditional All-Microwave Reset of a Superconducting Qubit
• Measurement-induced state transitions in a superconducting qubit: Beyond the rotating wave approximation
• Quantum logic gates for coupled superconducting phase qubits
• Exact steady state of a Kerr resonator with one- and two-photon driving and dissipation: Controllable Wigner-function multimodality and dissipative phase transitions
• Heralded state preparation in a superconducting qubit
• Initialization by measurement of a two-qubit superconducting circuit
• Tunable Superconducting Qubits with Flux-Independent Coherence
• Protocols for optimal readout of qubits using a continuous quantum nondemolition measurement
• Fast readout and reset of a superconducting qubit coupled to a resonator with an intrinsic Purcell filter
• Gated conditional displacement readout of superconducting qubits
• Improved Superconducting Qubit Readout by Qubit-Induced Nonlinearities
• Realizing Quantum Convolutional Neural Networks on a Superconducting Quantum Processor to Recognize Quantum Phases
• High-fidelity controlled-Z gate with maximal intermediate leakage operating at the speed limit in a superconducting quantum processor
• Dynamics of Transmon Ionization
• Fault tolerant architectures for superconducting qubits
• Transmon qubit readout fidelity at the threshold for quantum error correction without a quantum-limited amplifier
• Driven-dissipative quantum Kerr resonators: new exact solutions, photon blockade and quantum bistability
• High-fidelity measurement of qubits encoded in multilevel superconducting circuits
• Active resonator reset in the nonlinear dispersive regime of circuit QED
• Measurement-Induced State Transitions in a Superconducting Qubit: Within the Rotating Wave Approximation
• General method for extracting the quantum efficiency of dispersive qubit readout in circuit QED
• Broadband Filters for Abatement of Spontaneous Emission in Circuit Quantum Electrodynamics
• Fast high fidelity quantum non-demolition qubit readout via a non-perturbative cross-Kerr coupling
• Model-based Optimization of Superconducting Qubit Readout
• Photon-noise-tolerant dispersive readout of a superconducting qubit using a nonlinear Purcell filter
• Cloaking a qubit in a cavity
• Dispersive readout of a flux qubit at the single photon level
• Optimization of the resonator-induced phase gate for superconducting qubits

Cited by in corpus (33)

• Fast single atom imaging for optical lattice arrays
• Fast Flux-Activated Leakage Reduction for Superconducting Quantum Circuits
• Fast multiplexed superconducting qubit readout with intrinsic Purcell filtering
• Benchmarking the readout of a superconducting qubit for repeated measurements
• Accelerating Quantum Relaxation via Temporary Reset: A Mpemba-Inspired Approach
• Mitigating Losses of Superconducting Qubits Strongly Coupled to Defect Modes
• Optimal control in large open quantum systems: the case of transmon readout and reset
• Measurement-induced state transitions in dispersive qubit readout schemes
• 99.9%-fidelity in measuring a superconducting qubit
• Enhanced Qubit Readout via Reinforcement Learning
• Josephson traveling-wave parametric amplifier based on low-intrinsic-loss coplanar lumped-element waveguide
• Benchmarking Quantum Computers: Towards a Standard Performance Evaluation Approach
• Offset Charge Dependence of Measurement-Induced Transitions in Transmons
• Characterization of drive-induced unwanted state transitions in superconducting circuits
• Realizing Lattice Surgery on Two Distance-Three Repetition Codes with Superconducting Qubits
• Robustness of longitudinal transmon readout to ionization
• Generation of Frequency-Tunable Shaped Single Microwave Photons Using a Fixed-Frequency Superconducting Qubit
• Balanced cross-Kerr coupling for superconducting qubit readout
• Nonvolatile Cryogenic Phase Slip Memory with Single-Shot Readout
• Above 99.9% Fidelity Single-Qubit Gates, Two-Qubit Gates, and Readout in a Single Superconducting Quantum Device
• Wireless Josephson parametric amplifier above 20 GHz
• Gatemon Qubit Revisited for Improved Reliability and Stability
• Pure kinetic inductance coupling for cQED with flux qubits
• Multimode Purcell Filter for Superconducting-Qubit Reset and Readout with Intrinsic Purcell Protection
• Flexible Readout and Unconditional Reset for Superconducting Multi-Qubit Processors with Tunable Purcell Filters
• Non-demolition fluorescence readout and high-fidelity unconditional reset of a fluxonium qubit via dissipation engineering
• Mitigating Measurement Crosstalk via Pulse Shaping
• Dispersive Qubit Readout with Intrinsic Resonator Reset
• Mitigating state transition errors during readout with a synchronized flux pulse
• Quasiparticle-induced decoherence of a driven superconducting qubit
• Review of Superconducting Qubit Devices and Their Large-Scale Integration
• Low-rank optimal control of quantum devices
• Exploring the Fidelity of Flux Qubit Measurement in Different Bases via the Quantum Flux Parametron