Moving beyond the transmon: Noise-protected superconducting quantum circuits

Abstract

Artificial atoms realized by superconducting circuits offer unique opportunities to store and process quantum information with high fidelity. Among them, implementations of circuits that harness intrinsic noise protection have been rapidly developed in recent years. These noise-protected devices constitute a new class of qubits in which the computational states are largely decoupled from local noise channels. The main challenges in engineering such systems are simultaneously guarding against both bit- and phase-flip errors, and also ensuring high-fidelity qubit control. Although partial noise protection is possible in superconducting circuits relying on a single quantum degree of freedom, the promise of complete protection can only be fulfilled by implementing multimode or hybrid circuits. This Perspective reviews the theoretical principles at the heart of these new qubits, describes recent experiments, and highlights the potential of robust encoding of quantum information in superconducting qubits.

References in corpus (78)

• 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
• Surface codes: Towards practical large-scale quantum computation
• Hardware-efficient Variational Quantum Eigensolver for Small Molecules and Quantum Magnets
• Supervised learning with quantum enhanced feature spaces
• Coherent control of macroscopic quantum states in a single-Cooper-pair box
• Circuit Quantum Electrodynamics
• A Quantum Engineer's Guide to Superconducting Qubits
• Introduction to Quantum Noise, Measurement and Amplification
• Manipulating the Quantum State of an Electrical Circuit
• Encoding a qubit in an oscillator
• Superconducting Qubits: Current State of Play
• State preservation by repetitive error detection in a superconducting quantum circuit
• Quantum information processing with superconducting circuits: a review
• Fluxonium: single Cooper pair circuit free of charge offsets
• Decoherence in a superconducting quantum bit circuit
• Dynamically protected cat-qubits: a new paradigm for universal quantum computation
• Building logical qubits in a superconducting quantum computing system
• Realization of Three-Qubit Quantum Error Correction with Superconducting Circuits
• The Flux Qubit Revisited to Enhance Coherence and Reproducibility
• Suppressing Charge Noise Decoherence in Superconducting Charge Qubits
• New material platform for superconducting transmon qubits with coherence times exceeding 0.3 milliseconds
• Controlling the spontaneous emission of a superconducting transmon qubit
• Epitaxy of Semiconductor-Superconductor nanowires
• Tunable Supercurrent Through Semiconductor Nanowires
• Quantum Manipulations of Small Josephson Junctions
• A blueprint for demonstrating quantum supremacy with superconducting qubits
• The Kerr-Cat Qubit: Stabilization, Readout, and Gates
• A Semiconductor Nanowire-Based Superconducting Qubit
• Engineering the quantum states of light in a Kerr-nonlinear resonator by two-photon driving
• Quantum noise in the Josephson charge qubit
• Implementing a strand of a scalable fault-tolerant quantum computing fabric
• Realization of microwave quantum circuits using hybrid superconducting-semiconducting nanowire Josephson elements
• Implementation of low-loss superinductances for quantum circuits
• Superconducting Gatemon Qubit based on a Proximitized Two-Dimensional Electron Gas
• Topologically protected quantum bits from Josephson junction arrays
• Protected gates for superconducting qubits
• Superconducting Nanocircuits for Topologically Protected Qubits
• Protected Qubits and Chern Simons theories in Josephson Junction Arrays
• Pairing of Cooper Pairs in a Fully Frustrated Josephson Junction Chain
• Low- and high-frequency noise from coherent two-level systems
• Experimental realization of an intrinsically error-protected superconducting qubit
• Possible realization of an ideal quantum computer in Josephson junction array
• Observation of classical-quantum crossover of 1/f flux noise and its paramagnetic temperature dependence
• Evidence for coherent quantum phase-slips across a Josephson junction array
• Universal fast flux control of a coherent, low-frequency qubit
• Realization of a $\Lambda$ system with metastable states of a capacitively-shunted fluxonium
• Charging effects in the inductively shunted Josephson junction
• Characterization and reduction of microfabrication-induced decoherence in superconducting quantum circuits
• Measurement-induced qubit state mixing in circuit QED from up-converted dephasing noise
• Nanowire Superinductance Fluxonium Qubit
• Protecting a superconducting qubit from energy decay by selection rule engineering
• A Parity-Protected Superconductor-Semiconductor Qubit
• Characterizing and optimizing qubit coherence based on SQUID geometry
• Superconducting circuit protected by two-Cooper-pair tunneling
• The superconducting quasicharge qubit
• Coherence properties of the 0-$\pi$ qubit
• Protected Josephson Rhombi Chains
• A perspective on semiconductor-based superconducting qubits
• Aharonov-Casher-Effect Suppression of Macroscopic Tunneling of Magnetic Flux
• Bifluxon: Fluxon-Parity-Protected Superconducting Qubit
• Entanglement genesis by ancilla-based parity measurement in 2D circuit QED
• Anomalous Charge Noise in Superconducting Qubits
• Engineering Dynamical Sweet Spots to Protect Qubits from 1/$f$ Noise
• Surpassing the resistance quantum with a geometric superinductor
• Suppressed Charge Dispersion via Resonant Tunneling in a Single-Channel Transmon
• Observation of vanishing charge dispersion of a nearly-open superconducting island
• Understanding degenerate ground states of a protected quantum circuit in the presence of disorder
• A fluxonium-based artificial molecule with a tunable magnetic moment
• Spectroscopic Evidence of the Aharonov-Casher effect in a Cooper Pair Box
• Floquet-engineered enhancement of coherence times in a driven fluxonium qubit
• Control and Coherence Time Enhancement of the 0-$\pi$ Qubit
• Theory of 4e versus 2e supercurrent in frustrated Josepshon-junction rhombi chain
• Tuned transition from quantum to classical for macroscopic quantum states
• Positive- and negative-frequency noise from an ensemble of two-level fluctuators
• Spectrum and Coherence Properties of the Current-Mirror Qubit
• Coherent transport in Josephson-Junction rhombi chain with quenched disorder

Cited by in corpus (74)

• Engineered Dissipation for Quantum Information Science
• The Josephson diode effect in supercurrent interferometers
• Probing quantum devices with radio-frequency reflectometry
• Stabilizing a Bosonic Qubit using Colored Dissipation
• Advances in Bosonic Quantum Error Correction with Gottesman-Kitaev-Preskill Codes: Theory, Engineering and Applications
• Superconducting resonators with voltage-controlled frequency and nonlinearity
• Double-Fourier engineering of Josephson energy-phase relationships applied to diodes
• Geometric superinductance qubits: Controlling phase delocalization across a single Josephson junction
• Consistent Quantization of Nearly Singular Superconducting Circuits
• Gate-tunable kinetic inductance in proximitized nanowires
• Entangling transmons with low-frequency protected superconducting qubits
• Multi-mode architectures for noise-resilient superconducting qubits
• A superconducting qubit with noise-insensitive plasmon levels and decay-protected fluxon states
• Large Second-Order Josephson Effect in Planar Superconductor-Semiconductor Junctions
• Cloaking a qubit in a cavity
• Stabilizing and improving qubit coherence by engineering noise spectrum of two-level systems
• Quantum circuits with multiterminal Josephson-Andreev junctions
• Symplectic geometry and circuit quantization
• Shaping photons: quantum computation with bosonic cQED
• A quantum dot in germanium proximitized by a superconductor
• Engineering unsteerable quantum states with active feedback
• Analysis of arbitrary superconducting quantum circuits accompanied by a Python package: SQcircuit
• Analytic approach to transport in superconducting junctions with arbitrary carrier density
• Quantum phase slips in a resonant Josephson junction
• The hybrid Josephson rhombus: A superconducting element with tailored current-phase relation
• Gatemonium: A Voltage-Tunable Fluxonium
• Lecture Notes on Quantum Electrical Circuits
• Ultrahigh-inductance materials from spinodal decomposition
• Revealing the Origin and Nature of the Buried Metal-Substrate Interface Layer in Ta/Sapphire Superconducting Films
• Voltage-controlled synthesis of higher harmonics in hybrid Josephson junction circuits
• Homological Quantum Rotor Codes: Logical Qubits from Torsion
• Hardware implementation of quantum stabilizers in superconducting circuits
• Efficient decoupling of a non-linear qubit mode from its environment
• Phase Diffusion in Low-$E_J$ Josephson Junctions at milli-Kelvin Temperatures
• High-Order Qubit Dephasing at Sweet Spots by Non-Gaussian Fluctuators: Symmetry Breaking and Floquet Protection
• The Floquet Fluxonium Molecule: Driving Down Dephasing in Coupled Superconducting Qubits
• Effect of dilute impurities on short graphene Josephson junctions
• Protected Solid-State Qubits
• 1/f noise in quantum nanoscience
• Dephasing in Fluxonium Qubits from Coherent Quantum Phase Slips
• Subgap states in semiconductor-superconductor devices for quantum technologies: Andreev qubits and minimal Majorana chains
• Spectral Signatures of Non-Trivial Topology in a Superconducting Circuit
• Flux-pulse-assisted Readout of a Fluxonium Qubit
• Charge-parity switching effects and optimisation of transmon-qubit design parameters
• High-impedance resonators for strong coupling to an electron on helium
• Coherent errors in stabilizer codes caused by quasistatic phase damping
• Fast ZZ-Free Entangling Gates for Superconducting Qubits Assisted by a Driven Resonator
• Tunneling of fluxons via a Josephson resonant level
• Bit-flip errors in dissipative cat qubits: second-order perturbation theory
• Arresting Quantum Chaos Dynamically in Transmon Arrays
• Sub-Harmonic Control of a Fluxonium Qubit via a Purcell-Protected Flux Line
• Flux-charge symmetric theory of superconducting circuits
• Integrating Quantum Processor Device and Control Optimization in a Gradient-based Framework
• Frozonium: Freezing Anharmonicity in Floquet Superconducting Circuits
• Stochastic theory of nonlinear electrical circuits in thermal equilibrium
• Optimizing for periodicity: a model-independent approach to flux crosstalk calibration for superconducting circuits
• Viewing protected superconducting qubits through the lens of the cat qubit
• Non-Abelian holonomy of Majorana zero modes coupled to a chaotic quantum dot
• Parity-protected superconducting qubit based on topological insulators
• Power-law banded random matrix ensemble as a model for quantum many-body Hamiltonians
• Resilient superconducting-element design with genetic algorithms
• Non-reciprocal scattering in a microwave frequency comb
• Protected phase gate for the $0$-$\pi$ qubit using its internal modes
• Simulation of a rapid qubit readout dependent on the transmission of a single fluxon
• Non-demolition fluorescence readout and high-fidelity unconditional reset of a fluxonium qubit via dissipation engineering
• Andreev spin qubit protected by Franck-Condon blockade
• Intrinsic and induced quantum quenches for enhancing qubit-based quantum noise spectroscopy
• Review of Superconducting Qubit Devices and Their Large-Scale Integration
• Engineering Strong Beamsplitter Interaction between Bosonic Modes via Quantum Optimal Control Theory
• Entanglemons: Cross-platform protected qubits from entanglement
• Gate- and flux-tunable sin(2$\phi$) Josephson element with proximitized Ge-based junctions
• Robust multi-mode superconducting circuit optimized for quantum information processing
• Protected hybrid superconducting qubit in an array of gate-tunable Josephson interferometers
• Systematic Construction of Time-Dependent Hamiltonians for Microwave-Driven Josephson Circuits