Measurement-induced qudit geometric discord
Piotr Ługiewicz, Andrzej Frydryszak, Lech Jakóbczyk · Journal of Physics A Mathematical and Theoretical · 2017
Abstract We study measurement-induced geometric discord based on the trace norm and generalize some properties known for qutrits to qudits. Previous preliminary results for bipartite qutrit systems (i.e. d = 3 systems) are here strictly proved for arbitrary d . The present study supports the observations, coming also from other approaches, that systems with d ⩾ 3 show similar behaviour when quantum correlations are concerned, but there is pronounced difference between d = 2 and d = 3. Qubit systems are exceptionally simple. The underlying geometry of state spaces and related Lie groups is responsible for this.