mindquantum.core.gates.PhaseDampingChannel

class mindquantum.core.gates.PhaseDampingChannel(gamma: float, **kwargs)

A phase damping channel.

Phase damping channel express error that qubit loses quantum information without exchanging energy with environment.

Phase damping channel applies noise as:

\[\begin{split}\begin{gather*} \epsilon(\rho) = E_0 \rho E_0^\dagger + E_1 \rho E_1^\dagger \\ \text{where}\ {E_0}=\begin{bmatrix}1&0\\ 0&\sqrt{1-\gamma}\end{bmatrix}, \ {E_1}=\begin{bmatrix}0&0\\ 0&\sqrt{\gamma}\end{bmatrix} \end{gather*}\end{split}\]

where \(\rho\) is quantum state as density matrix type; \(\gamma\) is the coefficient of quantum information loss.

Parameters

gamma (int, float) – damping coefficient.

Examples

>>> from mindquantum.core.gates import PhaseDampingChannel
>>> from mindquantum.core.circuit import Circuit
>>> circ = Circuit()
>>> circ += PhaseDampingChannel(0.02).on(0)
>>> print(circ)
      ╔═════════════╗
q0: ──╢ PDC(γ=1/50) ╟───
      ╚═════════════╝

define_projectq_gate()

Define the corresponded projectq gate.

get_cpp_obj()

Get underlying C++ object.

matrix()

Kraus operator of the quantum channel.

Returns

list, contains all Kraus operators of this quantum channel.