cirq.bit_flip

Construct a BitFlipChannel that flips a qubit state with probability p.

cirq.bit_flip(
    p: Optional[float] = None
) -> Union[cirq.XPowGate, cirq.BitFlipChannel]

Used in the notebooks

Used in the tutorials

If p is None, this returns a guaranteed flip in the form of an X operation.

This channel evolves a density matrix via

$$
\rho \rightarrow M_0 \rho M_0^\dagger + M_1 \rho M_1^\dagger
$$

With

$$
\begin{aligned}
M_0 =& \sqrt{p} \begin{bmatrix}
                    1 & 0 \\
                    0 & 1
               \end{bmatrix}
\\
M_1 =& \sqrt{1-p} \begin{bmatrix}
                    0 & 1 \\
                    1 & -0
                 \end{bmatrix}
\end{aligned}
$$

p the probability of a bit flip.

ValueError if p is not a valid probability.