Functional Overview

This chapter provides the overview of the features provided by the SHFQA Instrument. The first section contains the description of the functional diagram and the hardware and software feature list. The next section details the front panel and the back panel of the measurement instrument. The following section provides product selection and ordering support.

Features

The SHFQA Instrument consists of several internal units that process digital data (light blue color) and several interface units processing analog signals (dark blue color). The front panel is depicted on the left-hand side and the back panel is depicted on the right-hand side. The arrows between the panels and the interface units indicate selected physical connections and the data flow. Information indicated in orange is linked to options that can be either ordered at purchase or upgraded later. The SHFQA Quantum Analyzer 8.5 GHz comes in a 2-channel and a 4-channel variant, providing either 2 or 4 readout channels, respectively. The ordering guide details the available upgrade options for each instrument type and whether the option can be upgraded directly in the field.

shfqa functional diagram
Figure 1. SHFQA instrument functional diagram

Each channel has signal generation (Readout Pulse Generator, Oscillator) and signal analysis (Sweeper, Qubit Measurement Unit) functionality, as well as common shared modules such as the 4-channel Monitor Scope, the Hardware Trigger Engine or shared communications (32-bit DIO, ZSync). The digital, complex-valued signal from the signal generation is up-converted to microwave frequencies in the analog domain using the Signal Output Module. After passing through the device under test, the analog signal is first down-converted and then digitized in the Signal Input Unit before the complex-valued signal is being analyzed.

The SHFQA can be configured in two modes:

Qubit Readout

In the Qubit Readout mode, the Readout Pulse Generator outputs the sum of up to 16 individual, user-defined arbitrary waveforms that are stored in separate Waveform Memory blocks. In the Qubit Measurement Unit, the signal is then first integrated using up to 16 user-defined, complex-valued Integration Weight Memories. The results of the integration are then discriminated between different qubit states, and the results are forwarded to other instruments in real time using either the 32-bit DIO or the ZSync links.

Spectroscopy

In the Spectroscopy mode, the Sweeper controls an Oscillator, hence a single frequency microwave signal is sent to the experiment. The Qubit Measurement Unit then correlates this signal to the original oscillator signal and displays transmission data in the Sweeper module.

Super-high-frequency Signal Inputs

  • Low-noise SHF Inputs, 0.5 - 8.5 GHz frequency range, 1 GHz bandwidth

  • Broadband double super-heterodyne frequency down-conversion

  • Calibrated (Input) Power Range, selectable from -45 dBm to 10 dBm

Super-high-frequency Signal Outputs

  • Low-noise SHF Outputs, 0.5 - 8.5 GHz frequency range, 1 GHz bandwidth

  • Broadband double super-heterodyne frequency up-conversion

  • Calibrated (Output) Power Range, selectable from -30 dBm to 10 dBm

Readout Pulse Generator

  • Arbitrary Waveform capability

  • Advanced sequencing

    • looping, branching

    • command table

    • advanced trigger control (time-staggered readout capability)

  • up to 16 waveform memory blocks with 4 kSa (total 64 kSa) memory, freely configurable

Qubit Measurement Unit

  • up to 16 complex integrators with programmable Integration Weight memory (for the 2-channel SHFQA, this requires the SHFQA-16W option.)

  • Multistate Discrimination

  • Correlator of discretized measurement results

  • Result Logger

Sweeper

  • Controls the numerical Oscillator for fast frequency sweeps in Spectroscopy mode

  • Displays the oscillator-correlated complex-valued data

Monitor Scope

  • shared between all Channels to view Input Signals

  • displays up to 4 complex signals

Hardware Trigger Engine

  • shared between all Channels and modes

  • 2 Marker Outputs and Trigger Inputs per Channel

High-speed Connectivity

  • SMA connectors on front and back panel for triggers, signals and external clock

  • USB 3.0 high-speed host interface

  • Maintenance USB connection

  • LAN/Ethernet 1 Gbit/s controller interface

  • DIO: 32-bit digital input-output port

  • 2 ZSync connectors for clock synchronization and fast data transfer

  • Clock input/output connectors (10 MHz)

Software Features

  • Web-based, high-speed user interface with multi-instrument control

  • Data server with multi-client support

  • API for C, LabVIEW, MATLAB, Python based instrument programming

  • Turnkey software and firmware features for fast system tune-up

Front Panel Tour

The front panel SMA connectors and control LEDs are arranged as shown in Figure 2 and listed in Table 1.

shfqa4 front panel with letters
Figure 2. SHFQA Quantum Analyzer 8.5 GHz front panel
Table 1. SHFQA Quantum Analyzer front panel description
Position Label / Name Description

A

Aux In

analog Auxiliary Input, max. 10 V

B

Out

single-ended waveform Signal Output, 0.5-8.5 GHz, max. 10 dBm

C

Mark

TTL Marker Outputs A and B

D

Trig

TTL Trigger Inputs A and B

E

In

single-ended waveform Signal Input, 0.5-8.5 GHz, max. 10 dBm

F

multicolor LEDs

off

Instrument off or uninitialized

blink

all LEDs blink for 5 seconds → indicator used by the Identify Device functionality

Busy

unused

Ext Ref

off

External Reference Signal not present/detected

blue

External Reference Signal is present and locked on to

yellow

External Reference Signal present, but not locked on to

red

External Reference Signal present, but lock failed

ZSync

off

no connection

blue
  • steady: ZSync fully connected AND synchronized

  • blinking: ZSync synchronized but not yet fully connected

yellow

ZSync plugged in, but not connected

red

ZSync interface error

Status

off

Instrument off or uninitialized

blue

Instrument is initialized and has no warnings or errors

yellow

Instrument has warnings

red

Instrument has errors

G

on off

Soft power button

Power button with incorporated status LED

off

Instrument off and disconnected from mains power

blue
  • flashing rapidly (>1/sec): Firmware is starting

  • flashing slow (<1/sec): Firmware ready, waiting for connection

  • constant: Instrument ready and active connection over USB or Ethernet

red
  • breathing: Instrument off but connected to mains power → safe to power off using the rear panel switch, or restart using the soft power button

  • flashing: Instrument booting up

  • constant: Fatal error occurred

Back Panel Tour

The back panel is the main interface for power, control, service and connectivity to other ZI instruments. Please refer to Figure 3 and Table 2 for the detailed description of the items.

shfqa back panel with letters
Figure 3. SHFQA Instrument back panel
Table 2. SHFQA Instrument back panel description
Position Label / Name Description

A

safety chassis gnd

Earth ground

4 mm banana jack connector for earth ground, electrically connected to the chassis and the earth pin of the power inlet

B

AC 100 - 240 V

Power inlet, fuse holder, and power switch

C

MDS 1

SMA: bidirectional TTL ports for multi-device synchronization

D

MDS 2

SMA: bidirectional TTL ports for multi-device synchronization

E

Maintenance

Universal Serial Bus (USB) 3.0 port for maintenance and instrument control

F

LAN 1GbE

1 Gbit LAN connector for instrument control

G

DIO 32bit

32-bit digital input/output (DIO) connector

H

USB

Universal Serial Bus (USB) 3.0 port connector → do not use for standard operation

I

ZSync Secondary

Secondary inter-instrument synchronization bus connector - Attention: This is not an Ethernet plug, connection to an Ethernet network might damage the instrument.

J

ZSync Primary

Primary inter-instrument synchronization bus connector - Attention: This is not an Ethernet plug, connection to an Ethernet network might damage the instrument.

K

External Clk In

External Reference Clock Input (10 MHz/100 MHz) for synchronization with other instruments

L

External Clk Out

External Reference Clock Output (10 MHz/100 MHz) for synchronization with other instruments

Ordering Guide

Table 3 provides an overview of the available SHFQA products. Upgradeable features are options that can be purchased anytime without the need to send the Instrument back to Zurich Instruments.

Table 3. SHFQA Instrument product codes for ordering
Product code Product name Description Field upgrade possible

SHFQA

SHFQA Quantum Analyzer

Base 2-channel Super-High-Frequency Quantum Analyzer (SHFQA)

-

SHFQA-16W

SHFQA-16W Integration Weights Extension Option

Option for 2-channel SHFQA

yes

SHFQA

SHFQA Quantum Analyzer

Base 4-channel Super-High-Frequency Quantum Analyzer (SHFQA)

-

Table 4. Product selector SHFQA
Feature SHFQA
2 channels
SHFQA
2 channels
+ SHFQA-16W
SHFQA
4 channels

Number of Readout Channels

(Readout Channel = Readout Pulse Generator + Qubit Measurement Unit)

2

2

4

Number of integration weights per channel

8

16

16

Number of integration weights total

16

32

64

Oscillators

2

2

4

Mixer-calibration-free analog frequency conversion

(double super-heterodyne)

yes

yes

yes

Frequency range

0.5-8.5 GHz

0.5-8.5 GHz

0.5-8.5 GHz

Total number of Markers/Triggers

(2 each per channel)

4/4

4/4

8/8

Vertical resolution Input/Output

14 bit

14 bit

14 bit

Digital IQ modulation

yes

yes

yes

ZSync capability

yes

yes

yes

Sequencing

yes

yes

yes

USB 3.0

yes

yes

yes

LAN 1 Gbit/s

yes

yes

yes