Parametrically controlled chiral interface for superconducting quantum devices

Abstract

Nonreciprocal microwave routing plays a crucial role for measuring quantum circuits, and allows for realizing cascaded quantum systems for generating and stabilizing entanglement between non-interacting qubits. The most commonly used tools for implementing directionality are ferrite-based circulators. These devices are versatile, but suffer from excess loss, a large footprint, and fixed directionality. For utilizing nonreciprocity in scalable quantum circuits it is desirable to develop efficient integration of low-loss and in-situ controllable directional elements. Here, we report the design and experimental realization of a minimal controllable directional interface that can be directly coupled to superconducting qubits. In the presented device, nonreciprocity is realized through a combination of interference and phase-controlled parametric pumping. We have achieved a maximum directionality of around 30\,dB, and the performance of the device is predicted quantitatively from independent calibration measurements. Using the excellent agreement of model and experiment, we predict that the circuit will be useable as a chiral qubit interface with inefficiencies at the one-percent level or below. Our work offers a promising route for realizing high-fidelity signal routing and entanglement generation in all-to-all connected microwave quantum networks, and provides a path for isolator-free qubit readout schemes.

23 pages, 15 figures

References in corpus (24)

• Surface codes: Towards practical large-scale quantum computation
• Chiral Quantum Optics
• Coupling Superconducting Qubits via a Cavity Bus
• Nonreciprocal Photon Transmission and Amplification via Reservoir Engineering
• Real-time quantum error correction beyond break-even
• Time-reversal symmetry breaking in circuit-QED based photon lattices
• Quantum Optics of Chiral Spin Networks
• Dispersive regime of circuit QED: photon-dependent qubit dephasing and relaxation rates
• Designing frequency-dependent relaxation rates and Lamb shift for a giant artificial atom
• Nonreciprocal microwave signal processing with a Field-Programmable Josephson Amplifier
• On-Demand Directional Microwave Photon Emission Using Waveguide Quantum Electrodynamics
• The QICK (Quantum Instrumentation Control Kit): Readout and control for qubits and detectors
• Fast readout and reset of a superconducting qubit coupled to a resonator with an intrinsic Purcell filter
• Universal stabilization of a parametrically coupled qubit
• Widely tunable on-chip microwave circulator for superconducting quantum circuits
• Chiral Quantum Network with Giant Atoms
• Generation of two-giant-atom entanglement in waveguide-QED systems
• Introduction to quantum non-reciprocal interactions: from non-Hermitian Hamiltonians to quantum master equations and quantum feedforward schemes
• Passive superconducting circulator on a chip
• Josephson parametric circulator with same-frequency signal ports, 200 MHz bandwidth, and high dynamic range
• Exact Results for a Boundary-Driven Double Spin Chain and Resource-Efficient Remote Entanglement Stabilization
• Tunable directional photon scattering from a pair of superconducting qubits
• Wideband Josephson Parametric Isolator
• Directional emission of a readout resonator for qubit measurement

Cited by in corpus (4)

• Hidden time-reversal in driven XXZ spin chains: exact solutions and new dissipative phase transitions
• Highly efficient microwave storage and retrieval using a superconducting chiral $\Lambda$-type molecule
• Autonomous stabilization of remote entanglement in a cascaded quantum network
• Predicted third-order sweet spots for phi-junction Josephson parametric amplifiers