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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:

$$\begin{array}{r}\begin{array}{c}ϵ(\rho )=E_0\rho E_0^{†}+E_1\rho E_1^{†}\\ \text{where}{E}_0=\left[\begin{array}{cc}1& 0\\ 0& \sqrt{1-\gamma }\end{array}\right],E_1=\left[\begin{array}{cc}0& 0\\ 0& \sqrt{\gamma }\end{array}\right]\end{array}\end{array}$$

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.