一般指標

信號產生器和信號輸出

波形生成

量子分析儀信號輸出

讀取脈衝產生器

量子分析儀信號輸入

量子位元測量單元

數位標記和触發

1 所有的儲存單元均可自由配置和觸發。每個單元最優對應4096個複值取樣點。

Introduction
The SHFQC Qubit Controller can control, read out and provide fast feedback on up to 6 superconducting qubits. It integrates the functionality of the SHFQA Quantum Analyzer, the SHFSG Signal Generator and more in a single instrument. With integrated microwave generation, a trigger distribution unit and the ultrafast feedback of 350 ns between all channels, simple microwave connections between the SHFQC and a cryostat are sufficient to start advanced qubit measurements. To provide flexibility for systems with a small number of qubits, the SHFQC comes in three possible configurations, in which either 2, 4, or 6 of the signal generator channels are enabled. For the 2- and 4-channel configurations, additional signal generator channels can be enabled in the field. As a result, the setup is fully software-controlled and can be reconfigured as needed to match the experimental requirements.

SHFQC Qubit Controller
Each control channel of the SHFQC has its own powerful sequencer for creating phase- and timing-programmable waveforms, so that a single SHFQC can control or couple qubits with pulses from DC to 8.5 GHz, and react at any time on measurements from the readout channel. With the SHFQC-16W upgrade option, the readout channel's freely configurable integration weights and readout-pulse memories are doubled from 8 to 16. This provides more flexibility in configuring the readout, e.g. by enabling full real-time control and readout of 6 qutrits.

Advanced features such as a real-time oscilloscope, fast spectroscopy, and the pulse-level sequencing capability allow users to further speed up their system tune-up and measurements.

The SHFQC integrates into the Zurich Instruments Quantum Computing Control System (QCCS) and is intuitively operated through the LabOne QCCS Software. This enables a seamless combination with other instruments such as the HDAWG for fast flux or gate voltage signals up to 750 MHz. Within a larger QCCS, the SHFQC enables access to fast local and global feedback as well as to error correction protocols for 100 qubits and beyond.

Applications
Quantum computing applications

• Coherent control of qubits through single and multi-qubit gates
• Frequency-multiplexed readout
• Dispersive single-shot readout
• Fast qubit and resonator spectroscopy, and setup characterization
• Real-time, low-latency feedback for system-wide operations and error correction protocols

Supported qubit types

• Superconducting qubits
• Spin qubit/superconducting resonator hybrids
• Qubits, qutrits and ququads

Other applications

• Amplifier noise characterization
• Microwave setup calibration

Highlights
High-fidelity qubit manipulation and readout
Operating over a range that extends up to 8.5 GHz, the SHFQC's double superheterodyne up- and down-conversion scheme relies on filtering rather than on interference, so that it performs over a wider frequency band and with better linearity than standard IQ-mixer-based conversion approaches. This capability is combined with the performance of synthesizers specifically designed for high-fidelity qubit control and readout, offering low phase noise and low timing jitter across the whole output frequency range. As a result, the SHFQC generates spurious-free, stable signals within an instantaneous bandwidth of 1 GHz and without requiring its users to spend time on mixer calibration or system maintenance.

When reading out multiple qubits through resonators coupled to the same readout line, even small spurs can lead to a confusing or smaller readout signal if they are sub-optimally located. The superheterodyne scheme of the SHFQC affords more flexibility on the design of resonator frequencies for frequency-multiplexed qubit readout. Furthermore, the combination with a linear amplification chain allows users to drive all single- and multi-qubit gates within short time intervals and free of distortion. The integrated frequency conversion offered by the SHFQC ensures that qubit control and readout operations realize the full potential of a quantum processor in terms of fidelity.

Efficient workflow and resource handling
The SHFQC's Signal Generator and Quantum Analyzer channels support minimal use of waveform data even when complex signals are required. Users provide the desired signals in the form of pulse descriptions to program the SHFQC in the most memory-efficient manner. Even for many-qubit systems that rely on multiple SHFQCs, this approach ensures that complex tune-up and calibration routines are completed within a minimum of instrument communication time. For example, the support of loops and conditional branching points enables the implementation of active reset in 350 ns as well as more complex quantum error-correction codes; real-time phase and frequency updates make it possible to implement virtual Z gates. With up to 98 kSa waveform memory per channel, the ability to handle up to 32k sequence instructions, and a sampling rate of 2 GSa/s, the SHFQC provides customizable multi-channel AWG signals for qubit control and readout.