NQCH Quantum Cloud Client

Install

Install first the package dependencies with the following commands.

We recommend to start with a fresh virtual environment to avoid dependencies conflicts with previously installed packages.

python -m venv ./env
source activate ./env/bin/activate

The nqch-quantum package can be installed through pip:

pip install nqch-quantum

Quick start

Once installed, the provider allows to run quantum circuit computations on NQCH CQT's labs.

:warning: Note: to run jobs on the remote cluster it is mandatory to own a validated account. Please, sign up to your preferred institution to obtain the needed token to run computations on the cluster.

The following snippet provides a basic usage example. Replace the your-token string with your user token received during the registration process. To check which devices are available with your account please visit the dashboard at your institution.

import qibo
import nqch_quantum

# create the circuit you want to run
circuit = qibo.models.QFT(5)

# authenticate to server through the client instance
token = "your-token"
client = nqch_quantum.Client(token)

# run the circuit
device = "device_name"
project = "project_name"
job = client.run_circuit(circuit, device=device, project=project, nshots=1024)
result = job.result()
print(result)

The device name indicates the specific system or machine that will process the job. The project name corresponds to the project or group to which the user belongs and which will be charged for the service usage.

Qibo backend

The package also exposes a Qibo backend provider, so circuits can be submitted using Qibo's backend API.

import qibo
from qibo import Circuit, gates

qibo.set_backend(
    "nqch-quantum",
    token="your-token",
    platform="selected_platform",
    project="project_name",
    verbosity=False,
)

circuit = Circuit(2)
circuit.add(gates.H(0))
circuit.add(gates.CNOT(0, 1))
circuit.add(gates.M(0, 1))

result = circuit(nshots=1024)
print(result.frequencies())

Direct backend execution is also supported when a per-call verbatim flag is needed.

backend = qibo.get_backend()
result = backend.execute_circuit(circuit, nshots=1024, verbatim=True)

Backend limitations

The NQCH backend submits circuits to remote hardware or cloud systems. Execution is shot-based and starts from the device default initial state, so initial_state is not supported. Exact statevector workflows, gradients, autodiff, and local statevector expectations are not generally supported by this backend.