The Zurich Instruments UHFQA Quantum Analyzer is a unique instrument for parallel readout of up to 10 superconducting or spin qubits with highest speed and fidelity. The UHFQA operates on a frequency span of up to ±600 MHz with nanosecond timing resolution, and it features 2 signal inputs and outputs for IQ base-band operation. Thanks to its low-latency signal processing chain of matched filters, real-time matrix operations, and state discrimination, the UHFQA supports the development of ambitious quantum computing projects for 100 qubits and more.
600 MHz Quantum Analyzer
- 1.8 GSa/s, ±600 MHz measurement range by single-sideband modulation
- 12-bit dual-channel input, 14-bit dual-channel AWG
- Parallel readout of up to 10 qubits
- Configurable matched filters, signal conditioning, crosstalk suppression, threshold operations
- LabOne® control software and APIs for Python, C, MATLAB®, LabVIEW™ and .NET
- Quantum computing
- Superconducting qubits
- Semiconductor spin qubits
- Frequency-multiplexed readout
- Single-shot qubit readout
- Active qubit reset
- Qubit spectroscopy
- Rabi oscillations
Fast readout with high fidelity
The UHFQA performs pulsed measurements to determine the transmission amplitude and phase of the device under test. There exist two methods to maximize the signal-to-noise ratio (SNR): pulse shaping and matched filtering. Pulse shaping with an arbitrary waveform generator minimizes the ring-up and ring-down time even for a device with slow response. The step response of the UHFQA's digital filters can be matched to the transient response of the device by programming a 4-kSa-long weight function for each filter. Compared to a simple unweighted integration, applying a properly matched filter significantly improves the SNR.
Scalable quantum setup
Measuring 10 qubits on a single microwave line means optimizing the cryogenic amplification chain. A configurable 10×10 matrix signal processor enables systematic suppression of crosstalk and, consequently, relaxed tolerances in device fabrication. In combination with the HDAWG, several UHFQAs constitute a fully synchronized instrumentation layer for qubit control and readout in the quantum stack. The low-latency 32-bit DIO interface enables feed-forward of the multi-qubit state for quantum error correction, in particular.
The UHFQA is controlled by LabOne and its APIs for Python, C, MATLAB®, LabVIEW™ and .NET. An extended example library in Python facilitates straightforward integration into established measurement frameworks. Thanks to the data structuring and processing functionality provided by the LabOne Data Server, the user part of the software stack remains simple and easy to maintain.
Qubit measurement unit
|Filter memory||4096 Sa/channel|
|Real-time matrix operations||1× deskew (2×2 real)
10× rotation (2×2 real)
1x crosstalk suppression (10×10 complex)
|Matrix elements||Range -1 to +1
|Data logger||Memory 1 MSa
Max. 217 averages
|Monitoring scope memory||4096 Sa/channel, 2 channels|
|Monitoring scope averaging||Max. 215 averages|
|Statistics unit||Count number of logical 1 in bit pattern
Count number of transitions in bit pattern
UHF signal inputs
|Frequency range||DC - 600 MHz|
|Input impedance||50 Ω or 1 MΩ || 18 pF|
|Input voltage noise||4 nV/√Hz above 100 kHz|
|Input ranges||±10 mV to ±1.5 V|
|A/D conversion||12 bits, 1.8 GSa/s|
Arbitrary waveform generator
|D/A conversion||14 bits, 1.8 GSa/s|
|Output ranges||±150 mV, ±1.5 V (high-impedance load)
-12.5 dBm, +7.5 dBm (50 Ω load)
|Waveform memory||128 MSa/channel (main)
32 kSa/channel (cache)
The UHFQA is designed for readout methods based on pulsed, time-integrated measurement of a radio-frequency signal on timescales from tens of nanoseconds to a few milliseconds. This covers, notably, dispersive readout of superconducting qubits in a circuit QED architecture as well as some RF-reflectometry methods used to read out semiconductor spin qubits.
The UHFQA does not have the counter functionality that is typically required for trapped-ion qubit measurements. For these experiments, we recommend the HDAWG Arbitrary Waveform Generator, which combines multi-channel AWG functionality with a pulse counter. The UHFQA is also not designed for measurement schemes based on DC voltage or current measurements, nor on methods relying on the detection of electron tunneling events.
No, the upgrade options available for the UHFLI and UHFAWG are not available for the UHFQA. However, the arbitrary waveform generator of the UHFQA is identical to the UHF-AWG Arbitrary Waveform Generator.
The UHFQA connects to the PQSC Programmable Quantum System Controller with the 32-bit DIO VHDCI interface. This enables transfer of qubit readout results to the PQSC. The UHFQA can also connect to the HDAWG Arbitrary Waveform Generator with the 32-bit VHDCI interface. This can be useful for basic feed-forward protocols. Due to the different voltage levels (5 V of the UHFQA and 3.3 V of the HDAWG), a voltage divider is required in this case. Please contact Zurich Instruments for further information.
No. The UHFQA can be controlled, and its measurement data obtained, with a conventional computer. The measurement data for real-time processing can be transmitted as a basic parallel TTL signal to custom digital electronics in the same way as they can be sent to the PQSC.
No. The UHFQA can be triggered by any conventional arbitrary waveform generator or by an internal trigger source.
The UHFQA comes with the LabOne software and its APIs for Python, LabVIEW, MATLAB, C, and .NET. A Python driver for the open-source QuCoDeS measurement framework is available, but please note that this driver is not maintained by Zurich Instruments. The examples of Python APIs included with the software are guided by the qubit readout application and enable fast integration into other measurement frameworks.
Its purpose is to compensate for signal crosstalk and IQ mixer phase imbalance.
Their purpose is to transform the signal after the integration for each qubit so that the signal is in one signal quadrature only.
Its purpose is to eliminate the effects of unwanted coupling between circuit elements on the quantum computing chip, e.g. coupling from one qubit to the readout resonator of another qubit.