ZZ freedom in two qubit gates

Abstract

Superconducting qubits on a circuit exhibit an always-on state-dependent phase error. This error is due to sub-MHz parasitic interaction that repels computational levels from non-computational ones. We study a general theory to evaluate the `static' repulsion between seemingly idle qubits as well as the `dynamical' repulsion between entangled qubits under microwave driving gate. By combining qubits of either the same or opposite anharmonicity signs we find the characteristics of static and dynamical ZZ freedoms. The latter universally eliminate the parasitic repulsion, leading us to mitigate high fidelity gate operation. Our theory introduces new opportunities for making perfect entangled and unentangled states which is extremely useful for quantum technology.

13 pages

References in corpus (9)

• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
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• Low-decoherence flux qubit
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• Reducing unitary and spectator errors in cross resonance with optimized rotary echoes
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• Superconducting qubits beyond the dispersive regime

Cited by in corpus (26)

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• Scalable Method for Eliminating Residual $ZZ$ Interaction between Superconducting Qubits
• Suppression of static ZZ interaction in an all-transmon quantum processor
• Extensive characterization of a family of efficient three-qubit gates at the coherence limit
• Double-Transmon Coupler: Fast Two-Qubit Gate with No Residual Coupling for Highly Detuned Superconducting Qubits
• Accurate methods for the analysis of strong-drive effects in parametric gates
• Tunable coupler to fully decouple and maximally localize superconducting qubits
• Single Shot i-Toffoli Gate in Dispersively Coupled Superconducting Qubits
• Experimental error suppression in Cross-Resonance gates via multi-derivative pulse shaping
• An error-protected cross-resonance switch in weakly-tuneable architectures
• Combating fluctuations in relaxation times of fixed-frequency transmon qubits with microwave-dressed states
• Non-perturbative analytical diagonalization of Hamiltonians with application to coupling suppression and enhancement in cQED
• Entangling interactions between artificial atoms mediated by a multimode left-handed superconducting ring resonator
• Collateral coupling between superconducting resonators: Fast and high fidelity generation of qudit-qudit entanglement
• Quantum heat valve and entanglement in superconducting $LC$ resonators
• Globally driven superconducting quantum computing architecture
• Lattice Hamiltonians and Stray Interactions Within Quantum Processors
• Scalable protocol to mitigate $ZZ$ crosstalk in universal quantum gates
• Perturbative Analysis of Quasi-periodic Patterning of Transmon Quantum Computers: Enhancement of Many-Body Localization
• Error mitigation of entangled states using brainbox quantum autoencoders
• Concurrent Fermionic Simulation Gate
• Parity Cross-Resonance: A Multiqubit Gate