  Separability and entanglement for n-qubits systems are quantified by using
Hilbert-Schmidt (HS) decompositions in which the density matrices are
decomposed into various terms representing certain one qubit, two-qubits,and
larger qubits measurements. The present method is more general than previous
methods for bipartite systems as it can be used for quantification of
entanglement for large n-qubits systems.We demonstrate the use of such method
by analyzing three qubits GHZ states, and three qubits general Bell states
produced by a certain multiplications of Braid operators, operating on the
computational basis of states. Quantum correlations are obtained by measuring
all qubits of these systems, while a measurement of a part of the system gives
only classical correlations. Quantification of entanglement for these systems
is given by the use of HS decompositions.
