We explore sufficient conditions for inseparability in mixed states with a globally conserved charge, such as particle number. argue that even separable may contain entanglement fixed charge sectors, long the state cannot be separated into charge-conserving components. As witness of symmetric we study number (NE), $\mathrm{\ensuremath{\Delta}}{S}_{m}$, defined entropy change due to subsystem's ...

We show that the presence of finite-size monopoles can lead to a number of interesting physical processes involving quantum entanglement of charges. Taking as a model the classical solution of the N = 2 SU(2) Yang-Mills theory, we study interaction between dyons and scalar particles in the adjoint and fundamental representation. We find that there are bound states of scalars and dyons, which, r...

In the quest of completely describing entanglement in the general case of a finite number of parties sharing a physical system of finite dimensional Hilbert space a new entanglement magnitude is introduced for its pure and mixed states: robustness. It corresponds to the minimal amount of mixing with locally prepared states which washes out all entanglement. It quantifies in a sense the endurenc...

2 3 N + o(N) of the number of queries for any parallel scheme with unentangled input states. With the assistance of entanglement, we obtain a general lower bound 1 2 (N − √ N). We provide concrete examples to illustrate our results. In particular, we show that the case of N = 6 can be solved exactly with only two queries by using a bipartite entangled input state. Our results indicate that in t...

Entanglement of the excitonic states in the system of two coupled semiconductor microcrystallites, whose sizes are much larger than the Bohr radius of exciton in bulk semiconductor but smaller than the relevant optical wavelength, is quantified in terms of the entropy of entanglement. It is observed that the nonlinear interaction between excitons increases the maximum values of the entropy of t...

An important problem in quantum information theory is the quantification of entanglement in multipartite mixed quantum states. In this work, a connection between the geometric measure of entanglement and a distance measure of entanglement is established. We present a new expression for the geometric measure of entanglement in terms of the maximal fidelity with a separable state. A direct applic...

We study the entanglement transfer from a two-mode continuous variable system (initially in the two-mode SU(2) cat states) to a couple of discrete two-state systems (initially in an arbitrary mixed state), by use of the resonant Jaynes-Cummings (JC) interaction. We first quantitatively connect the entanglement transfer to non-Gaussianity of the two-mode SU(2) cat states and find a positive corr...