Quantum noisy channel modeled by canonical unitary operation in two qubits

In this work, we analyze the entanglement variation of pure bipartite states during quantum noisy channel propagation. The quantum noisy channel is modeled by the interaction between the bipartite state and the environment through a canonical unitary form of a two-qubit gate. We have found an analytical expression for the entanglement of the bipartite state at the channel output as function of the channel parameters. At last, we used numerical simulation to show that a canonical unitary form of a three qubit gate is not a good model for a quantum noisy channel.