We present classes of monogamy inequalities related to the ?th () power entanglement measure based on unified-() entropy, and polygamy ?th assistance by using Hamming weight. show that these are tighter than existing ones. Detailed examples given for illustrating advantages.

We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of enta...