Verifying the analogy between transversely coupled spin-1/2 systems and inductively-coupled fluxoniums
arXiv:2407.15450 · doi:10.1088/1367-2630/adb77b
Abstract
We report a detailed characterization of two inductively coupled superconducting fluxonium qubits for implementing high-fidelity cross-resonance gates. Our circuit stands out because it behaves very closely to the case of two transversely coupled spin-1/2 systems. In particular, the generally unwanted static ZZ-term due to the non-computational transitions is nearly absent despite a strong qubit-qubit hybridization. Spectroscopy of the non-computational transitions reveals a spurious LC-mode arising from the combination of the coupling inductance and the capacitive links between the terminals of the two qubit circuits. Such a mode has a minor effect on our specific device, but it must be carefully considered for optimizing future designs.
References in corpus (30)
- Superconducting Qubits: Current State of Play
- Quantum information processing with superconducting circuits: a review
- Procedure for systematically tuning up crosstalk in the cross resonance gate
- A simple all-microwave entangling gate for fixed-frequency superconducting qubits
- A tunable coupling scheme for implementing high-fidelity two-qubit gates
- Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits
- Introduction to Quantum Electromagnetic Circuits
- A universal gate for fixed-frequency qubits via a tunable bus
- Realization of high-fidelity CZ and ZZ-free iSWAP gates with a tunable coupler
- Suppression of Qubit Crosstalk in a Tunable Coupling Superconducting Circuit
- Process verification of two-qubit quantum gates by randomized benchmarking
- High-fidelity, high-scalability two-qubit gate scheme for superconducting qubits
- Demonstration of weight-four parity measurements in the surface code architecture
- Microwave-induced coupling of superconducting qubits
- Demonstration of a High-Fidelity CNOT for Fixed-Frequency Transmons with Engineered ZZ Suppression
- Fluxonium: an alternative qubit platform for high-fidelity operations
- Implementation of Conditional-Phase Gates based on tunable ZZ-Interactions
- High-Fidelity, Frequency-Flexible Two-Qubit Fluxonium Gates with a Transmon Coupler
- Demonstration of a Tuneable Coupler for Superconducting Qubits Using Coherent, Time Domain, Two-Qubit Operations
- Diabatic gates for frequency-tunable superconducting qubits
- High-fidelity controlled-Z gate with maximal intermediate leakage operating at the speed limit in a superconducting quantum processor
- Selective darkening of degenerate transitions demonstrated with two superconducting quantum bits
- Scalable High-Performance Fluxonium Quantum Processor
- Scqubits: a Python package for superconducting qubits
- Quantum crosstalk cancellation for fast entangling gates and improved multi-qubit performance
- Hardware-Efficient Microwave-Activated Tunable Coupling Between Superconducting Qubits
- Fast logic with slow qubits: microwave-activated controlled-Z gate on low-frequency fluxoniums
- Programmable Heisenberg interactions between Floquet qubits
- Microwave-Activated Controlled-Z Gate for Fixed-Frequency Fluxonium Qubits
- Native approach to controlled-Z gates in inductively coupled fluxonium qubits