QRM-RF
======
.. _qrm_rf_description:
Description
---------------
The RF iteration of the Qubit Readout Module (QRM-RF) provides all necessary
capabilities for qubit readout without the need to manually up and down convert
signals. This allows for the device to synthesize and acquire signals in the
range of 2-18.5GHz using internal RF conversion stages.
.. figure:: ./figures/QBLOX_CLUSTER_FRONTAL_QRM-RF.jpg
:height: 600px
:align: left
:alt: QRM-RF front panel
On the front of a QRM-RF module you will find the following components:
- **2 x SMA female (receptacle) connectors**: 1 output (O\ :sup:`[1]`: @ 50 Ω) ; and 1 input channel (I\ :sup:`[1]`: @ 50 Ω).
- **2 x SMP male (pin) connectors**: Marker output channels (0-3.3 V TTL).
- **6 x status LEDs**: See section :ref:`cluster_leds`.
The operation of the module is similar to the standard QRM, with 6 Q1 sequence processors onboard.
Each sequencer is connected to the output markers, as well as the input and
output paths. Using parametrization, each sequencer can target one qubit for readout, allowing
multiplexed readout of multiple qubits on the same channel. The AWG paths can
generate the readout pulses and the acquisition paths can process the returned
readout data. The acquisition path supports any combination of three acquisition modes:
- `Scope`: Returns the raw input data.
- `Integration`: Returns the result after integrating the input data;
optionally based on an integration function stored in memory.
- `Thresholded`: Returns the binary qubit value after thresholding
the integrated value.
The results of the acquisitions are returned to the user through the
qblox_instruments driver.
For a list of available features please go to :ref:`qrm_rf_features`
For an overview of applications please go to :ref:`qrm_rf_applications`
.. _qrm_rf_block_diagram:
Block Diagram
-------------
.. figure:: ./figures/QRM_RF_Block_Diagram.svg
:alt: Block diagram of a Qubit Readout Module
The QRM-RF module contains the following features:
.. list-table::
:widths: 100 100
:header-rows: 0
* - :ref:`qrm_rf_10MHz_reference`
- :ref:`qrm_rf_trigger`
* - :ref:`qrm_rf_SYNQ`
- :ref:`qrm_rf_LINQ`
* - :ref:`qrm_rf_Q1_sequencers`
- :ref:`qrm_rf_marker_output_channels`
* - :ref:`qrm_rf_sequencer_multiplexer`
- :ref:`qrm_rf_digital_offset`
* - :ref:`qrm_rf_DAC_and_ADC`
- :ref:`qrm_rf_offset_DAC`
* - :ref:`qrm_rf_local_oscillator`
- :ref:`qrm_rf_IQ_mixer`
* - :ref:`qrm_rf_variable_attenuator`
- :ref:`qrm_rf_output_switch`
.. _qrm_rf_features:
Features
--------
.. _qrm_rf_10MHz_reference:
1. 10MHz Reference
^^^^^^^^^^^^^^^^^^
Alongside all modules available, the QRM-RF module operates with respect
to a 10MHz reference provided by the cluster.
.. _qrm_rf_trigger:
2. Trigger
^^^^^^^^^^
The trigger of the QRM-RF is connected to the cluster and allows for fast
synchronization between modules.
.. _qrm_rf_SYNQ:
3. SYNQ
^^^^^^^^^^^^^^^^^
The Qblox SYNQ technology enables simple and quick synchronization over multiple
instruments, allowing for modules to be started synchronously << 1ns.
See section :ref:`synchronization`
for more information.
.. _qrm_rf_LINQ:
4. LINQ
^^^^^^^
The Qblox LINQ technology allows for the results of measurements to be shared
between devices, distributing outcomes in < 320ns.
.. _qrm_rf_Q1_sequencers:
5. Q1 Sequencer
^^^^^^^^^^^^^^^
The Q1 sequencers are the heart(s) of the QRM-RF instrument. They orchestrate
the experiment using a custom low-latency sequence processor specifically
designed
for quantum experiments. Each Q1 sequencer controls a dedicated AWG path and,
in the case of a QRM/QRM-RF, an acquisition path, which enables
parametrized pulse generation and readout. Each instrument has 6 of these
sequencers to target multiple qubits with one instrument. See section
:ref:`sequence_processor` for more information on how to
program and control them.
Each sequencer has a dedicated gain step for both path 0 and 1, which can be
statically configured using the :meth:`Sequencer.gain_awg_path0` parameters.
However, the gain can also be dynamically controlled using the `set_awg_gain`
instruction of the sequence processor which enables pulse parametrization
(see section :ref:`sequence_processor_operation_instructions`). The static and
dynamic gain controls are complementary.
.. note::
Since the QRM-RF module has integrated IQ mixing, the gain
:meth:`Sequencer.gain_awg_path0` has to be the same for both paths.
Each sequencer has a dedicated numerically controlled oscillator. The NCO can
be used to track the qubit or resonator phase (at a fixed frequency) and the IQ mixer can be
used to modulate the output.
The frequency of the NCO and phase can be statically controlled using the
:meth:`Sequencer.nco_freq` and :meth:`Sequencer.nco_phase_offs`
parameters. However, the phase of the NCO can also be dynamically controlled
using the `set_freq`, `reset_ph`, `set_ph` and `set_ph_delta` instructions of
the sequence processor, which enables
pulse parametrization and execution of virtual Z-gates (see section
:ref:`sequence_processor_operation_instructions`). The static and dynamic phase
control
is complementary. The modulation is enabled using the
:meth:`Sequencer.mod_en_awg` parameter. The demodulation is enabled using
the :meth:`Sequencer.demod_en_acq` parameter.
Each sequencer can perform averaging and binning of measurement
of results. Integration and state assignment of data can also be
performed on board, outcomes of these measurements can then be shared via LINQ
within 320ns.
.. _qrm_rf_marker_output_channels:
6. Marker output channels
^^^^^^^^^^^^^^^^^^^^^^^^^
Each sequencer has control over the four marker output channels, with the
control of each sequencer being OR'ed to create the final marker outputs.
The markers can be dynamically controlled with the `set_mrk` instruction of the
sequence processor (see section :ref:`sequence_processor_operation_instructions`),
but can also be overwritten with the static marker overwrite parameters
:meth:`Sequencer.marker_ovr_en` and :meth:`Sequencer.marker_ovr_value`.
The marker output range is 0-3.3 V TTL. In the QRM-RF module `set_mrk` is also used
to toggle the switches before the outputs/inputs to enable the respective
output/input.
For the QRM-RF module, bit indices 0 & 1 correspond to input 1 and output 1 switches respectively,
indices 2 & 3 correspond to marker outputs 1 and 2 respectively.
6.1 Setting Markers as Active HIGH/LOW
**************************************
The default state of marker is active high `(OFF = 0V, ON = 3.3V)`. Users
have the ability to change the marker output from active HIGH to active LOW `( OFF = 3.3 V, ON = 0V)`. It can be done
using the parameter :meth:`QRM_RF.marker0_inv_en`. This inversion of marker default states is possible for all marker
channels. Here `marker0` and `marker1` correspond to bit indices 2 & 3 respectively in in the argument
of `set_mrk` as mentioned above.
.. _qrm_rf_sequencer_multiplexer:
7. Sequencer Multiplexer
^^^^^^^^^^^^^^^^^^^^^^^^
A multiplexer that allows any sequencer to be connected to any output.
Multiple sequencers can also be connected to a single output. This, in
combination with the dedicated NCO per sequencer and the IQ mixer, enables easy and
flexible targeting of multiple resonators on a single channel.
See :ref:`sequence_processor_multiplexing` for more details.
.. note::
The output of each sequencer is complimentary. Be aware of potential output
clipping when connecting multiple sequencers to a single output.
.. _qrm_rf_digital_offset:
8. Digital Offset
^^^^^^^^^^^^^^^^^
Each sequencer has a dedicated offset step for both path 0 and 1, which can be
statically configured using the :meth:`Sequencer.offset_awg_path0` parameters.
However, the offset can also be dynamically controlled using the `set_awg_offs`
instruction of the sequence processor which enables pulse parametrization.
(see section :ref:`sequence_processor_operation_instructions`). The static and
dynamic offset controls are complementary.
.. note::
This offset is applied to the signals before the mixer and cannot be used
for DC offset correction if the mixer is enabled.
.. _qrm_rf_DAC_and_ADC:
9. DAC and ADC
^^^^^^^^^^^^^^
The dynamic output range of the QRM-RF's DACs is 5 Vpp and 50 Ω terminated at
1GBps.The maximum input range of the QRM's ADCs is 2 Vpp and 50 Ω terminated.
.. note::
The 12-bit ADCs have a fixed range of 2 Vpp. When performing acquisitions
the input should be an order of magnitude such that the resolution (0.5mV)
of the ADC can accurately define the measured signal.
Gain or attenuation stages may be required at the input to compensate for
this. See :ref:`qrm_rf_variable_attenuator` for the
attenuation onboard the device.
.. _qrm_rf_offset_DAC:
10. Offset DAC
^^^^^^^^^^^^^^
The offset DAC allows users to apply a DC offset to the output signal
without the risk of clipping the signal at the DAC.
.. _qrm_rf_local_oscillator:
11. Local Oscillator
^^^^^^^^^^^^^^^^^^^^
The QRM-RF module comes equipped with its own built-in local oscillator capable
of generating signals between 2.5 and 18GHz for IQ mixing.
.. _qrm_rf_IQ_mixer:
12. IQ Mixer
^^^^^^^^^^^^
The QRM-RF module also has onboard IQ mixers for both the output and
acquisition. The LO's of these internal mixing stages are capable
of sweeping between 2-18.5GHz. This allows for the generation and
acquisition of signals at the qubit and readout resonator frequency
respectively.
.. _qrm_rf_variable_attenuator:
13. Variable Attenuator
^^^^^^^^^^^^^^^^^^^^^^^
The QRM-RF module has a variable attenuator, which can be programmed, on both the input and output
terminals. The output attenuation can be programmed to be between 0 to 60 dB in 2 dB steps whilst
the input attenuation can be set between 0 to 30 dB in 2 dB steps.
.. _qrm_rf_output_switch:
14. Output Switch
^^^^^^^^^^^^^^^^^
The output terminal of the QRM-RF can be toggled with an inbuilt switch.
.. _qrm_rf_applications:
Applications
------------
The Qubit readout module is designed to be utilized for the measurement of qubits.
The experimental setup will vary depending on the device being controlled:
Superconducting Qubits
^^^^^^^^^^^^^^^^^^^^^^
The QRM-RF can be utilized to create a readout pulse with its outputs and corresponding acquisition
for a multi qubit device. Frequency division multiplexing can be utilized to readout
multiple qubit states simultaneously (up to 6). The outputs of a QRM-RF can also be utilized as arbitrary
outputs (e.g. for a charge line) if needed. As the QRM-RF module has an on-board IQ mixer
for both generation and acquisition it can interface directly with the drive and readout lines
of the circuit. The details of such a setup are provided
here: |qrm_rf_superconducting_qubits|.
.. |qrm_rf_superconducting_qubits| raw:: html
Superconducting Qubits
Spin Qubits
^^^^^^^^^^^
The QRM-RF provides readout capability for measuring spin qubits in GaAs, Si or Ge
quantum dots. The QRM-RF is capable of performing qubit measurements via charge
sensing, RF reflectometry, gate-based readout or via microwave resonators.
As the QRM-RF module has an on-board IQ mixer for both generation and acquisition
it can interface directly no external RF-mixing circuitry is required.
of the circuit. Details of potential setups and applications are available here:
|qrm_rf_spin_qubits|.
.. |qrm_rf_spin_qubits| raw:: html
Spin Qubits
NV-centers/Spins in Diamonds
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The QRM-RF can be used to perform measurements on spins in diamond by connecting
it to a qubits microwave resonator. The QRM-RF module will be able to synthesize
frequencies in the range required for readout. Details of potential setups and
applications are available here:
|qrm_rf_nv_qubits|.
.. |qrm_rf_nv_qubits| raw:: html
NV-centers
.. _qrm-rf_Abs_max_rat:
Absolute Maximum Ratings
------------------------
.. warning::
This section shows the absolute maximum ratings of the cluster QRM-RF module. Operation beyond these values can damage the module and cluster!
.. _qrm_rf_abs_max_input:
Input
^^^^^
+--------------------+------------+--------+-------+--------+
| Parameter | Condition | Min | Typ | Max |
+====================+============+========+=======+========+
| Input Power | | | | 15 dBm |
+--------------------+------------+--------+-------+--------+
.. _qrm_rf_specs:
Specifications
--------------
Output
^^^^^^
+--------------------+-------------+--------+-------+------+
| Parameter | Condition | Min | Typ | Max |
+====================+=============+========+=======+======+
| Number of channels | | | 1 | |
+--------------------+-------------+--------+-------+------+
| Output coupling | | | AC | |
+--------------------+-------------+--------+-------+------+
| DAC resolution | | | 12bits| |
+--------------------+-------------+--------+-------+------+
| Output impedance | | | 50Ω | |
+--------------------+-------------+--------+-------+------+
| Output power | In 50Ω load | -55dBm | | 5dBm |
+--------------------+-------------+--------+-------+------+
.. _qrm_rf_specs_input:
Input
^^^^^
+--------------------+------------+--------+-------+------+
| Parameter | Condition | Min | Typ | Max |
+====================+============+========+=======+======+
| Number of channels | | | 1 | |
+--------------------+------------+--------+-------+------+
| Input coupling | | | AC | |
+--------------------+------------+--------+-------+------+
| ADC Resolution | | | 12bits| |
+--------------------+------------+--------+-------+------+
| Input impedance | | | 50Ω | |
+--------------------+------------+--------+-------+------+
| Input power | | | | 5dBm |
+--------------------+------------+--------+-------+------+
Marker Outputs
^^^^^^^^^^^^^^
+-------------------+-------------+--------+-------+------+
| Parameter | Condition | Min | Typ | Max |
+===================+=============+========+=======+======+
| Number of markers | | | 4 | |
+-------------------+-------------+--------+-------+------+
| High voltage | high Z load | | 3.3V | |
+-------------------+-------------+--------+-------+------+
| Low voltage | | | 0.0V | |
+-------------------+-------------+--------+-------+------+