Qiskit IBM Quantum Provider

Qiskit is an open-source SDK for working with quantum computers at the level of circuits, algorithms, and application modules.

This module contains a provider that allows accessing the IBM Quantum
systems and simulators.

Installation

We encourage installing Qiskit via the PIP tool (a python package manager),
which installs all Qiskit elements and components, including this one.

pip install qiskit

PIP will handle all dependencies automatically for us and you will always
install the latest (and well-tested) version.

To install from source, follow the instructions in the
contribution guidelines.

Setting up the IBM Quantum Provider

Once the package is installed, you can access the provider from Qiskit.

Note: Since November 2019 (and with version 0.4 of this
qiskit-ibmq-provider package / version 0.14 of the qiskit package)
legacy Quantum Experience or QConsole (v1) accounts are no longer supported.
If you are still using a v1 account, please follow the steps described in
update instructions to update your account.

Configure your IBM Quantum Experience credentials

1. Create an IBM Quantum Experience account or log in to your existing account by visiting
   the IBM Quantum Experience login page.

2. Copy (and/or optionally regenerate) your API token from your
   IBM Quantum Experience account page.

3. Take your token from step 2, here called MY_API_TOKEN, and run:

   from qiskit import IBMQ
   IBMQ.save_account('MY_API_TOKEN')

   The command above stores your credentials locally in a configuration file called qiskitrc.
   By default, this file is located in $HOME/.qiskit, where $HOME is your home directory. If
   you are still using Qconfig.py, please delete that file and run the command above.

Accessing your IBM Quantum Experience backends

After calling IBMQ.save_account(), your credentials will be stored on disk.
Once they are stored, at any point in the future you can load and use them
in your program simply via:

from qiskit import IBMQ

provider = IBMQ.load_account()
backend = provider.get_backend('ibmq_qasm_simulator')

Alternatively, if you do not want to save your credentials to disk and only
intend to use them during the current session, you can use:

from qiskit import IBMQ

provider = IBMQ.enable_account('MY_API_TOKEN')
backend = provider.get_backend('ibmq_qasm_simulator')

By default, all IBM Quantum Experience accounts have access to the same, open project
(hub: ibm-q, group: open, project: main). For convenience, the
IBMQ.load_account() and IBMQ.enable_account() methods will return a provider
for that project. If you have access to other projects, you can use:

provider_2 = IBMQ.get_provider(hub='MY_HUB', group='MY_GROUP', project='MY_PROJECT')

Updating to the new IBM Quantum Experience

Since November 2019 (and with version 0.4 of this qiskit-ibmq-provider
package), the IBM Quantum Provider only supports the new IBM Quantum Experience, dropping
support for the legacy Quantum Experience and Qconsole accounts. The new IBM Quantum
Experience is also referred as v2, whereas the legacy one and Qconsole as v1.

This section includes instructions for updating your accounts and programs.
Please note that:

• the IBM Quantum Experience v1 credentials and the programs written for pre-0.3
  versions will still be working during the 0.3.x series. From 0.4 onwards,
  only v2 credentials are supported, and it is recommended to upgrade
  in order to take advantage of the new features.
• updating your credentials to the IBM Quantum Experience v2 implies that you
  will need to update your programs. The sections below contain instructions
  on how to perform the transition.

Updating your IBM Quantum Experience credentials

If you have credentials for the legacy Quantum Experience or Qconsole stored in
disk, you can make use of IBMQ.update_account() helper. This helper will read
your current credentials stored in disk and attempt to convert them:

from qiskit import IBMQ

IBMQ.update_account()

Found 2 credentials.
The credentials stored will be replaced with a single entry with token "MYTOKEN"
and the new IBM Quantum Experience v2 URL (https://auth.quantum-computing.ibm.com/api).

In order to access the provider, please use the new "IBMQ.get_provider()" methods:

  provider0 = IBMQ.load_account()
  provider1 = IBMQ.get_provider(hub='A', group='B', project='C')

Note you need to update your programs in order to retrieve backends from a
specific provider directly:

  backends = provider0.backends()
  backend = provider0.get_backend('ibmq_qasm_simulator')

Update the credentials? [y/N]

Upon confirmation, your credentials will be overwritten with a valid IBM Quantum
Experience v2 set of credentials. For more complex cases, consider deleting your
previous credentials via IBMQ.delete_accounts() and follow the instructions
in the IBM Quantum Experience account page.

Updating your programs

The new IBM Quantum Experience support also introduces a more structured approach for accessing backends.
Previously, access to all backends was centralized through:

IBMQ.backends()
IBMQ.get_backend('ibmq_qasm_simulator')

In version 0.3 onwards, the preferred way to access the backends is via a
Provider for one of your projects instead of via the global IBMQ instance
directly, allowing for more granular control over
the project you are using:

my_provider = IBMQ.get_provider()
my_provider.backends()
my_provider.get_backend('ibmq_qasm_simulator')

In a similar spirit, you can check the providers that you have access to via:

IBMQ.providers()

In addition, since the new IBM Quantum Experience provides only one set of
credentials, the account management methods in IBMQ are now in singular form.
For example, you should use IBMQ.load_account() instead of
IBMQ.load_accounts(). An IBMQAccountError exception is raised if you
attempt to use the legacy methods with an IBM Quantum Experience v2 account.

The following tables contains a quick reference for the differences between the
two versions. Please refer to the documentation of each method for more in
depth details:

Account management

Using backends

Contribution Guidelines

If you'd like to contribute to IBM Quantum Provider, please take a look at our
contribution guidelines. This project adheres to Qiskit's code of conduct.
By participating, you are expect to uphold to this code.

We use GitHub issues for tracking requests and bugs. Please use our slack
for discussion and simple questions. To join our Slack community use the
invite link at Qiskit.org. For questions that are more suited for a forum we
use the Qiskit tag in Stack Exchange.

Next Steps

Now you're set up and ready to check out some of the other examples from our
Qiskit Tutorial repository.

Authors and Citation

The Qiskit IBM Quantum Provider is the work of many people who contribute to the
project at different levels. If you use Qiskit, please cite as per the included
BibTeX file.

License

Apache License 2.0.