Entanglement behavior for different classes of two qubit systems passing
through a generalized amplitude damping channel is discussed. The phenomena of
sudden single, double changes and the sudden death of entanglement are reported
for correlated and non- correlated noise. It is shown that, for less entangled
states, these phenomena appear for small values of channel strength. The effect
of the channel can be frozen for these classes as one increases the channel
strength. Maximum entangled states are more fragile than partial entangled
states, where the entanglement decays very fast. However, one can not freeze
the effect of the noise channel for systems initially prepared in maximum
entangled states. The decay rate of entanglement for systems affected by
non-correlated noise is much larger than that affected by correlated noise
