200 citations · 1.2k across the 29 of their papers we have counts for
29 papers
Correlation constraints and the Bloch geometry of two qubits
Simon Morelli, Christopher Eltschka, Marcus Huber +1
We present a novel inequality on the purity of a bipartite state depending solely on the difference of the local Bloch vector lengths. For two qubits this inequality is tight for a…
The shape of higher-dimensional state space: Bloch-ball analog for a qutrit
Christopher Eltschka, Marcus Huber, Simon Morelli +1
Geometric intuition is a crucial tool to obtain deeper insight into many concepts of physics. A paradigmatic example of its power is the Bloch ball, the geometrical representation…
Maximum -body correlations do not in general imply genuine multipartite entanglement
Christopher Eltschka, Jens Siewert
The existence of correlations between the parts of a quantum system on the one hand, and entanglement between them on the other, are different properties. Yet, one intuitively woul…
Joint Schmidt-type decomposition for two bipartite pure quantum states
Christopher Eltschka, Jens Siewert
It is well known that the Schmidt decomposition exists for all pure states of a two-party quantum system. We demonstrate that there are two ways to obtain an analogous decompositio…
Dimensionally sharp inequalities for the linear entropy
Simon Morelli, Claude Klöckl, Christopher Eltschka +2
We derive an inequality for the linear entropy, that gives sharp bounds for all finite dimensional systems. The derivation is based on generalised Bloch decompositions and provides…
Exponentially many entanglement and correlation constraints for multipartite quantum states
Christopher Eltschka, Felix Huber, Otfried Gühne +1
We present a family of correlations constraints that apply to all multipartite quantum systems of finite dimension. The size of this family is exponential in the number of subsyste…