qkd_key_rate.base.keyrate module

Base class for KeyRate objects.

class qkd_key_rate.base.keyrate.AsymptoticKeyRateEstimate(detector, **kwargs)[source]

Bases: KeyRate

Asymptotic key rate base class

abstract compute_rate(*, mu, attenuation)[source]

Computes the key-rate given intensity-settings and an attenuation

Parameters:

  • mu (ArrayLike) – Used intensities

  • attenuation (float) – Attenuation of the channel

Return type:

float

Returns:

key-rate

Raises:

ValueError – When mu is given with invalid dimensions

class qkd_key_rate.base.keyrate.FiniteKeyRateEstimate(detector, **kwargs)[source]

Bases: KeyRate

Finite key rate base class

abstract compute_rate(*, mu, attenuation, probability_basis_X, probability_basis_Z, n_X=None)[source]

Computes the key-rate given intensity-settings and an attenuation

Parameters:

  • mu (ArrayLike) – Used intensities

  • attenuation (float) – Attenuation of the channel

  • probability_basis_X (ArrayLike) – Probabilities for each intensity in the X-basis

  • probability_basis_Z (ArrayLike) – Probabilities for each intensity in the Z-basis

  • n_X (Optional[int]) – Number of pulses in the X-basis. If not provided, will be estimated from gain, probability_basis_X and total number of pules.

Return type:

float

Returns:

key-rate

Raises:

ValueError – When mu is given with invalid dimensions

class qkd_key_rate.base.keyrate.KeyRate(detector, **kwargs)[source]

Bases: object

Key rate base class.

__init__(detector, **kwargs)[source]
Parameters:

  • detector (Detector) – The detector used at Bob’s side

  • kwargs (int) – Protocol specific input

abstract compute_rate(mu, attenuation, **kwargs)[source]

Computes the key-rate given intensity-settings and an attenuation

Parameters:

  • mu (ArrayLike) – Used intensities

  • attenuation (float) – Attenuation of the channel

  • kwargs (Any) – Depending on protocol more arguments can be supplied

Returns:

key-rate

Raises:

ValueError – When mu is given with invalid dimensions

abstract optimize_rate(*, attenuation, x_0=None, bounds=None)[source]

Find the parameter setting that achieves the highest possible key-rate

Parameters:

  • attenuation (float) – Loss in dB for the channel

  • x_0 (Optional[ArrayLike]) – Initial search value

  • bounds (Optional[List[ArrayLike]]) – Bounds on search range

Return type:

Tuple[float, float]

Returns:

Optimized intensity and key-rate

Raises:

  • ValueError – when x_0 or bounds are given with invalid dimensions.

  • ValueError – when the found key-rate is negative.