Quantum technologies often utilize quantum entanglement in order to gain advantage compared to classical technologies. Thus, the practical ability to detect entanglement and quantify its strength in a given system, is essential for the advancement of these technologies. In this talk, we rely on our previously established framework [1,2] to develop a new approach for detecting entanglement in mixed states. The first step in our method is based on simply measuring quantum correlations and constructing a certain correlation matrix – this, of course, is highly feasible. Moreover, this approach requires to measure a state-independent set of operators. The correlation matrix is then used for defining a family of parameters we term Correlation Minor Norms, which allow one to detect entanglement, and in many cases quantify it too. In addition, we illustrate a scheme which, we hypothesize, yields for each Correlation Minor Norm a separable state that maximizes it. This scheme involves constructing sets of "equiangular" pure states for both parties, generalizing properties of SIC-POVMs; this may be interpreted as a geometric observation regarding the nature of "the least separable" separable states. Finally, quantitative connections are made with entanglement entropy and quantum discord.

[1] A. Carmi and E. Cohen, Sci. Adv. 5, eaav8370 (2019).

[2] A. Te’eni, B. Y. Peled, E. Cohen, and A. Carmi, Phys. Rev. A 99, 040102 (2019).