Overview

The qilisdk.noise module contains classes that represent different types of noise in quantum systems. These noise models can be integrated into quantum simulations to account for real-world imperfections and decoherence effects. A NoiseModel can contains various types of noise, each of which is then applied during simulation.

Backend

Noise Models Supported

QiliSim

CudaBackend

QutipBackend

Usage

Noise passes are added to a NoiseModel, which should then be included when creating a backend. For example, to create a simple circuit and then simulate it with a CUDA backend containing a bit-flip noise model:

from qilisdk.noise import NoiseModel, BitFlip
from qilisdk.digital import X, Circuit
from qilisdk.functionals import DigitalPropagation
from qilisdk.readout import Readout
from qilisdk.backends import CudaBackend

# Define the random circuit and functional
c = Circuit(nqubits=2)
c.add(X(0))
c.add(X(1))
functional = DigitalPropagation(c)

# Apply bit-flip noise with 50% probability to X gates on qubit 1
nm = NoiseModel()
nm.add(BitFlip(probability=0.5), gate=X, qubits=[1])

# Execute with CUDA backend
backend_cuda = CudaBackend(noise_model=nm)
res = backend_cuda.execute(functional, readout=Readout().with_sampling(nshots=1000))
print(res)

Summary of Noise Types

Some of the noise passes available in QiliSDK can be used for both digital circuits and analog schedules, while others are specific to one or the other:

Noise Type

Digital Propogation

Analog Evolution

KrausChannel

LindbladGenerator

PauliChannel

BitFlip

PhaseFlip

Depolarizing

AmplitudeDamping

Dephasing

GaussianPerturbation

OffsetPerturbation

ReadoutAssignment