產品介紹∣600 MHz 量子分析儀

UHFQA 量子分析儀是市場上僅有的一款可並行、高速和高保真度讀取多至10 個超導或自旋量子位元的儀器。UHFQA 覆蓋的頻率寬度為1.2 GHz (±600 MHz)，時間分辨率在納秒量級。UHFQA 擁有2 個輸入通道和2 個輸出通道，用於IQ 調製操作。得益於低延遲的信號處理鏈路(包含匹配濾波器、實時矩陣操作，以及量子態鑑別)，UHFQA 與其它QCCS 儀器並用時，可支持擁有100 個甚至更多量子位元的量子計算機系統。

應用

超導量子位元
半導體自旋量子位元
量子計算
超導量子位元
半導體自旋量子位元
頻分複用讀取
單發量子位元讀取
主動量子位元重置
量子位元光譜
拉比振盪

特色
高保真度、高速量子位元讀取
UHFQA 以脈衝式測量待測樣品的透射幅度和相位，並通過脈衝整形和匹配濾波器來優化測量信噪比。通過任意波形產生器產生特定的波形可最小化待測樣品的振盪響應。UHFQA 數位濾波器的階躍響應可由可編程的權重函數(4 kSa/濾波器)來設定，因此可完全匹配待測樣品的瞬時響應。相對於簡單的非權重積分方案，使用合適的匹配濾波器可顯著提高測量的信噪比。

可擴展的量子設備
在單個微波線路上測量10 個量子位元要求優化低溫放大鍊路。可配置的10 x 10 矩陣信號處理器能夠抑制串擾，從而降低對器件製造公差的要求。UHFQA 量子分析儀可與HDAWG 結合使用構成完全同步的儀器層，用於量子堆棧中的量子態控制和讀出。低延遲的32 位DIO 接口可實現多量子態的前饋，特別是用於量子糾錯。

儀器控制軟體和編程工具
UHFQA 可以通過LabOne 及 APIs (Python、C、MATLAB ®、 LabVIEW™、及 .NET) 來控制。Python 的擴展範例庫便於用戶將其直接整合到已有的測量框架。LabOne 數據服務器提供了數據結構化和數據處理功能，因此軟體的用戶部分簡單且易維護。

量子測量單元

濾波器記憶體	4096 取樣點/通道
實時矩陣操作	1× 通道補償(2×2 實數) 10× 旋轉(2×2 實數) 1x 串擾抑制(10×10 複數)
矩陣元素	範圍-1 至+1 分辨率< 20e-6
數據記錄器	內存1 MSa 最多2 ¹⁷次平均
監視器內存	4096 取樣點/通道, 2 通道
監視器平均次數	最多2 ¹⁵ 次平均
統計單元	位元模式下邏輯為1 的次數位元模式下躍遷產生的次數

訊號輸入

頻率範圍	DC - 600 MHz
輸入阻抗	50 Ω 或1 MΩ \|\| 18 pF
輸入電壓噪聲	4 nV/√Hz ( > 100 kHz時)
輸入範圍	±10 mV 至±1.5 V
A/D 轉換	12 位, 1.8 GSa/s

任意波形產生器

通道數	2
標記	2個/通道
D/A 轉換	14 位, 1.8 GSa/s
輸出範圍	±150 mV, ±1.5 V (高阻) -12.5 dBm, +7.5 dBm (50 Ω 負載)
波形內存	128 MSa/通道(內存) 32 kSa/通道(高速暫存)

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.

Applications

Quantum computing
Superconducting qubits
Semiconductor spin qubits
Frequency-multiplexed readout
Single-shot qubit readout
Active qubit reset
Qubit spectroscopy
Rabi oscillations

Highlights
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.

Quantum-ready software
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 Resolution <20e-6
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

Channels	2
Markers	2/channel
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)