cirq.AsymmetricDepolarizingChannel

class cirq.AsymmetricDepolarizingChannel(p_x: float, p_y: float, p_z: float)

A channel that depolarizes asymmetrically along different directions.

__init__(p_x: float, p_y: float, p_z: float) → None

The asymmetric depolarizing channel.

This channel applies one of four disjoint possibilities: nothing (the

identity channel) or one of the three pauli gates. The disjoint

probabilities of the three gates are p_x, p_y, and p_z and the

identity is done with probability 1 - p_x - p_y - p_z. The supplied

probabilities must be valid probabilities and the sum p_x + p_y + p_z

must be a valid probability or else this constructor will raise a

ValueError.

This channel evolves a density matrix via

\rho -> (1 -p_x + p_y + p_z) \rho

+ p_x X \rho X + p_y Y \rho Y + p_z Z \rho Z

Parameters:

• p_x – The probability that a Pauli X and no other gate occurs.
• p_y – The probability that a Pauli Y and no other gate occurs.
• p_z – The probability that a Pauli Z and no other gate occurs.

Raises:

ValueError – if the args or the sum of args are not probabilities.

Methods

on(*qubits)	Returns an application of this gate to the given qubits.
validate_args(qubits)	Checks if this gate can be applied to the given qubits.