SQ-CARS: A Scalable Quantum Control and Readout System

Abstract

Qubits are the basic building blocks of a quantum processor which require electromagnetic pulses in giga hertz frequency range and latency in nanoseconds for control and readout. In this paper, we address three main challenges associated with room temperature electronics used for controlling and measuring superconducting qubits: scalability, direct microwave synthesis, and a unified user interface. To tackle these challenges, we have developed SQ-CARS, a system based on the ZCU111 evaluation kit. SQ-CARS is designed to be scalable, configurable, and phase synchronized, providing multi-qubit control and readout capabilities. The system offers an interactive Python framework, making it user-friendly. Scalability to a larger number of qubits is achieved by deterministic synchronization of multiple channels. The system supports direct synthesis of arbitrary vector microwave pulses using the second-Nyquist zone technique, from 4 to 9 GHz. It also features on-board data processing like tunable low pass filters and configurable rotation blocks, enabling lock-in detection and low-latency active feedback for quantum experiments. All control and readout features are accessible through an on-board Python framework. To validate the performance of SQ-CARS, we conducted various time-domain measurements to characterize a superconducting transmon qubit. Our results were compared against traditional setups commonly used in similar experiments. With deterministic synchronisation of control and readout channels, and an open-source approach for programming, SQ-CARS paves the way for advanced experiments with superconducting qubits.

arXiv comment15 pages, 13 figures

References in corpus (20)

• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
• Quantum Computing
• Charge insensitive qubit design derived from the Cooper pair box
• A Quantum Engineer's Guide to Superconducting Qubits
• Superconducting Qubits: Current State of Play
• Observation of high coherence in Josephson junction qubits measured in a three-dimensional circuit QED architecture
• Quantum feedback control of a superconducting qubit: Persistent Rabi oscillations
• Engineering cryogenic setups for 100-qubit scale superconducting circuit systems
• A four-qubit germanium quantum processor
• Quantum walks on a programmable two-dimensional 62-qubit superconducting processor
• Rapid high-fidelity multiplexed readout of superconducting qubits
• Trapped ion quantum computation with transverse phonon modes
• The QICK (Quantum Instrumentation Control Kit): Readout and control for qubits and detectors
• Scalable High-Performance Fluxonium Quantum Processor
• QubiC: An open source FPGA-based control and measurement system for superconducting quantum information processors
• Independent, extensible control of same-frequency superconducting qubits by selective broadcasting
• Using Spontaneous Emission of a Qubit as a Resource for Feedback Control
• FPGA-based electronic system for the control and readout of superconducting quantum processors
• ICARUS-Q: Integrated Control and Readout Unit for Scalable Quantum Processors
• IQ Mixer Calibration for Superconducting Circuits

Cited by in corpus (2)

• Qibosoq: an open-source framework for quantum circuit RFSoC programming
• Low-latency machine learning FPGA accelerator for multi-qubit-state discrimination