requsim.noise module

Classes:

NoiseChannel(n_qubits, channel_function)

Standardized way to define noise channels.

NoiseModel([channel_before, map_replace, ...])

Class for describing noise in a standardized way.

Functions:

freeze_noise_channel(noise_channel, *args, ...)

Turn NoiseChannel with variable arguments into a static noise channel.
class requsim.noise.NoiseChannel(n_qubits, channel_function)

Bases: object

Standardized way to define noise channels.

This class can be simply called to apply this channel on a state of the correct number of qubits, or you can use the apply_to method to let the noise channel handle its application for you.

Parameters

  • n_qubits (int) – This noise channel acts on n_qubits input qubits.

  • channel_function (callable) – The function describing the channel.

Variables

n_qubits –

Methods:

apply_to(rho, qubit_indices, *args, **kwargs)

Apply the noise channel to specified qubits of a state rho.
apply_to(rho, qubit_indices, *args, **kwargs)

Apply the noise channel to specified qubits of a state rho.

Parameters

  • rho (np.ndarray) – The density matrix the channel is applied to.

  • qubit_indices (list of ints) – Numbering of qubits runs from 0…n-1

  • *args (are handed through to the appropriate function) –

  • **kwargs (are handed through to the appropriate function) –

Returns

np.ndarray – The state after the channel has been applied.

class requsim.noise.NoiseModel(channel_before: Optional[NoiseChannel] = None, map_replace: Optional[callable] = None, channel_after: Optional[NoiseChannel] = None)

Bases: object

Class for describing noise in a standardized way.

Parameters

  • channel_before (NoiseChannel or None) – Channel that is applied before the operation. Default: None

  • map_replace (callable or None) – This noisy callable replaces whatever the operation tries to do. Default: None (May not be supported by all processes.)

  • channel_after (NoiseChannel or None) – Channel that is applied after the operation. Default: None

Variables

Attributes:

channel_before

map_replace

channel_after

channel_before: Optional[NoiseChannel] = None
map_replace: Optional[callable] = None
channel_after: Optional[NoiseChannel] = None
requsim.noise.freeze_noise_channel(noise_channel, *args, **kwargs)

Turn NoiseChannel with variable arguments into a static noise channel.

This is useful when the application of the channel is delayed, so the args and kwargs do not need to be stored separately until that happens.

Parameters

  • noise_channel (NoiseChannel) – Description of parameter noise_channel.

  • *args (type) – Description of parameter *args.

  • **kwargs (type) – Description of parameter **kwargs.

Returns

type – Description of returned object.