Purity distribution for bipartite random pure states
Olivier Giraud · Journal of Physics A Mathematical and Theoretical · 2007
Analytic expressions for the probability density distribution of the linear entropy and the purity are derived for bipartite pure random quantum states. The explicit distributions for a state belonging to a product of Hilbert spaces of dimensions p and q are given for p = 3 and any q ⩾ 3, as well as for p = q = 4.