Processing signals in a quantum computing system

Patent metadata

Field	Value
Publication number	US-10192168-B2
Application number	US-201515035615-A
Country	US
Kind code	B2
Filing date	Feb 27, 2015
Priority date	Feb 28, 2014
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

In some aspects, a quantum computing system includes a control system and a quantum processor cell. The control system generates quantum processor control information for a group of devices housed in the quantum processor cell, and each device in the group has a distinct operating frequency. In some cases, a waveform generator generates a multiplexed control signal based on the quantum processor control information, and the multiplexed control signal is communicated an input signal processing system. In some cases, the input signal processing system includes an input channel configured to receive the multiplexed control signal, a de-multiplexer configured to separate device control signals from the multiplexed control signal, and output channels configured to communicate the respective device control signals into the quantum processor cell.

First claim

The invention claimed is:

1. A quantum computing method comprising:
generating quantum processor control information for a group of devices housed in a quantum processor cell, each device in the group having a distinct operating frequency;
generating a multiplexed control signal based on the quantum processor control information;
communicating the multiplexed control signal from a first, higher temperature stage to a second, lower temperature stage, wherein the second temperature stage comprises a low-noise, cryogenic environment;
communicating the multiplexed control signal on a physical channel into an input signal processing system, the input signal processing system operating in the low-noise, cryogenic environment;
separating device control signals from the multiplexed control signal by de-multiplexing the multiplexed control signal in the input signal processing system, wherein the multiplexed control signal is de-multiplexed by a de-multiplexer device operating in the low-noise, cryogenic environment from an input channel onto multiple output channels, the output channels comprising a distinct physical channel for each device in the group; and
communicating the respective device control signals on the output channels into the quantum processor cell for the group of devices, the quantum processor cell operating in the low-noise, cryogenic environment.

2. The quantum computing method of claim 1 , wherein the first temperature stage comprises a room temperature stage.

3. The quantum computing method of claim 1 , comprising shielding the quantum processor cell against microwave and optical frequencies, wherein the shielding is performed by at least one of a metallic, superconducting, or lossy material.

4. The quantum computing method of claim 1 , wherein the multiplexed control signal comprises a microwave signal communicated by a microwave transmission line.

5. The quantum computing method of claim 1 , wherein the quantum processor control information comprises control sequences for the respective devices in the group, and each device control signal corresponds to one of the control sequences.

6. The quantum computing method of claim 1 , wherein the group of devices comprises a first group of devices that each have distinct operating frequencies in a frequency range, and the method comprises:
generating first quantum processor control information for the first group of devices;
generating second, distinct quantum processor control information for a second group of devices housed in a quantum processor cell, the second group each having distinct operating frequencies in the frequency range;
generating a first multiplexed control signal based on the first quantum processor control information;
generating a second, distinct multiplexed control signal based on the second quantum processor control information;
communicating the first multiplexed control signal on a first physical channel into the input signal processing system;
communicating the second multiplexed control signal on a second, distinct physical channel into the input signal processing system;
separating a first set of device control signals from the first multiplexed control signal by de-multiplexing the first multiplexed control signal in the input signal processing system;
separating a second, distinct set of device control signals from the second multiplexed control signal by de-multiplexing the second multiplexed control signal in the input signal processing system;
communicating the first set of device control signals into the quantum processor cell for the first group of devices; and
communicating the second set of device control signals into the quantum processor cell for the second group of devices.

7. The quantum computing method of claim 1 , wherein:
the quantum processor cell comprises a multi-dimensional array of qubit devices, the multi-dimensional array comprising sub-arrays associated with separate frequency bands, the qubit devices in each sub-array having a qubit operating frequency within the frequency band associated with the sub-array, and
the group of devices comprises a group of the qubit devices in the multi-dimensional array, and the group of qubit devices includes one qubit device in each of the sub-arrays.

8. A quantum computing system comprising:
a control system comprising:
one or more data processors configured to generate quantum processor control information for a group of qubit devices housed in a quantum processor cell that operates in a low-noise cryogenic environment, each qubit device in the group having a distinct operating frequency;
a waveform generator configured to generate a multiplexed control signal from the quantum processor control information;

a signal delivery system configured to communicate the multiplexed control signal from a first, higher temperature stage to a second, lower temperature stage, wherein the second temperature stage comprises the low-noise, cryogenic environment:
an input signal processing system that operates in the low-noise cryogenic environment and comprises:
an input channel configured to receive the multiplexed control signal;
a de-multiplexer device configured to separate device control signals from the multiplexed control signal; and
output channels configured to communicate the respective device control signals into the quantum processor cell for the group of qubit devices, the output channels comprising a distinct physical channel for each qubit device in the group; and

the quantum processor cell configured to receive the device control signals from the input signal processing system.

9. The quantum computing system of claim 8 , wherein the waveform generator comprises an arbitrary waveform generator configured to convert digital signals to analog signals.

10. The quantum computing system of claim 8 , wherein the multiplexed control signal comprises a microwave signal, and the quantum computing system comprises a microwave transmission line configured to communicate the multiplexed control signal.

11. The quantum computing method of claim 1 , wherein the group of devices comprises a group of qubit devices, the quantum processor control information comprises qubit control information for the group of qubit devices.

12. The quantum computing method of claim 1 , wherein the group of devices comprises a group of coupler devices, the quantum processor control information comprises coupler control information for the group of coupler devices.

13. The quantum computing method of claim 1 , wherein the group of devices comprises a group of readout devices, the quantum processor control information comprises readout control information for the group of readout devices.

14. The quantum computing system of claim 8 , wherein:
the quantum processor cell comprises a multi-dimensional array of qubit devices, the multi-dimensional array comprising sub-arrays associated with separate frequency bands, the qubit devices in each sub-array having a qubit operating frequency within the frequency band associated with the sub-array, and
the group of qubit devices comprises a group of the qubit devices in the multi-dimensional array, the group of qubit devices includes one qubit device in each of the sub-arrays.

15. A quantum computing method comprising:
receiving, at an output signal processing system operating in a low-noise, cryogenic environment, qubit readout signals from a group of readout devices housed in a quantum processor cell operating in the low-noise, cryogenic environment, each readout device in the group having a distinct readout frequency;
generating

Assignees

• Rigetti & Co Inc
• Rigetti & Co Inc

Inventors

• Rigetti Chad Tyler
• Thompson Dane Christoffer

Classifications

• G06N20/00 Primary

  Machine learning · CPC title

• G06F13/36 Primary

  for access to common bus or bus system · CPC title

• G06F15/80

  comprising an array of processing units with common control, e.g. single instruction multiple data processors (G06F15/82 takes precedence {; for correlation function computation G06F17/15}) · CPC title

• G06F13/4068

  Electrical coupling · CPC title

• G06N99/002 Primary

  Physics · mapped topic