Quantinuum

Note

Quantinuum has launched a new cloud-based platform called Quantinuum Nexus. Instructions for accessing Nexus will be sent to QCUP users in January 2025. QCUP users should transition to Nexus for a newer user dashboard experience. See the Quantinuum Nexus section for more details.

Overview

Quantinuum offers access to trapped ion quantum computers and emulators, accessible via their API and User Portal. For the complete set of currently available devices, qubit numbers, etc. see the Quantinuum Systems User Guide under the Examples tab on the legacy Quantinuum User Portal or the Backends tab on Nexus.

This guide describes how to use the system once you have access. For instructions on how to gain access, see our Quantum Access page instead.

Quantinuum’s documentation for both Nexus and the H-Series devices can be found here: https://docs.quantinuum.com/

Features

The complete set of Quantinuum System Model H1 and Model H2 hardware specifications and operations, can be found in their H-Series User Guide.

Features include, but are not limited to:

  • All-to-all connectivity

  • Laser based quantum gates

  • Linear trap Quantum Charge-Coupled Device (QCCD) architecture with three or more parallel gate zones

  • Mid-circuit measurement conditioned circuit branching

  • Qubit reuse after mid-circuit measurement

  • Native gate set: single-qubit rotations, two-qubit ZZ-gates

Connecting

Cloud Access

Users can access information about Quantinuum’s systems, view submitted jobs, look up machine availability, and update job notification preferences on the cloud dashboard on the legacy Quantinuum User Portal or Quantinuum Nexus.

Quantinuum Nexus

Quantinuum has launched a new cloud-based platform called Quantinuum Nexus.

OLCF JupyterHub

If you do not want to install Jupyter yourself, users can leverage OLCF’s JupyterHub service to help create a python environment to access Quantinuum systems.

Locally via pytket

Users are able to submit jobs that run remotely on Quantinuum’s systems from a local python development environment. Directions for setting up the python environment and getting started in a notebook locally as well as additional examples utilizing conditional logic and mid-circuit measurement are found under the Examples tab on the legacy Quantinuum User Portal or Quantinuum’s H-Series Getting Started page.

Running Jobs & Queue Policies

Information on submitting jobs to Quantinuum systems, system availability, checking job status, and tracking usage can be found in Quantinuum’s H-Series Workflow and Getting Started pages.

Users have access to the API validator to check program syntax, and to the Quantinuum System Model H1 and H2 emulators, which returns actual results back as if users submitted code to the real quantum hardware.

Note

A recommended workflow for running on Quantinuum’s quantum computers is to utilize the syntax checker first, run on the emulator, then run on one of the quantum computers.

Allocations & Credit Usage

Running a job on the System Model H1 family and System Model H2 hardware requires Quantinuum Credits. Additional information on credit usage for H-Series devices can be found in the H-Series User Guide. Due to increased demand and to make the most efficient use of credits, the following allocating policy will go into effect starting October 1st 2022:

  • Any request for credits must be submitted by the project Principle Investigator (PI) to help@olcf.ornl.gov

  • Requests for machine credits must be justified using results from the emulator to determine the appropriate amount needed. Requests without emulator-based justifications will be denied.

  • Requests will be evaluated based on the provided technical justification, programmatic efficiency, and machine availability. The effective usage of prior allocations by the project will also be considered.

  • Allocations will be granted on a monthly basis to maximize the availability of the H1 family and H2 machines. Please note that allocations do not carry over to the next month and must be consumed in the month granted.

  • Allocation requests requiring 20 qubits and fewer will be considered for H1 family machines, and allocation requests requiring 21 or more qubits will be considered for H2.

Allocation requests for the following month must be submitted no later than the 25th of the preceding month. The uptime schedule is available on the Calendar tab of the legacy Quantinuum User Portal, or by navigating to a specific backend in Nexus (e.g., for H1-1: https://nexus.quantinuum.com/backends/Quantinuum/H1-1 ).

Due to hardware emulation complexity, jobs using greater than 29 qubits for statevector emulation are likely to experience significantly slowed execution times.

Software

The TKET framework is a software platform for the development and execution of gate-level quantum computation, providing state-of-the-art performance in circuit compilation. It was created and is maintained by Quantinuum. The toolset is designed to extract the most out of the available NISQ devices of today and is platform-agnostic.

In python, the pytket package is available for python 3.10+. The pytket and pytket-quantinuum packages are included as part of the installation instructions on the user portal.

For more information, see the following links: