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arXiv · 1811.08125

Triangle-like inequalities related to coherence and entanglement negativity

Zhi-Xiang Jin·Xianqing Li-Jost·Shao-Ming Fei
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Abstract

Quantum coherence and entanglement are two key features in quantum mechanics and play important roles in quantum information processing and quantum computation. We provide a general triangle-like inequality satisfied by the $l_1$-norm measure of coherence for convex combination of arbitrary $n$ pure states of a quantum state $ρ$. Furthermore, we present triangle-like inequality for the convex-roof extended negativity for any states of rank 2, which gives a positive answer to a conjecture raised in [Phys. Rev. A 96, 062308 (2017)]. Detailed examples are given to illustrate the relations characterized by the triangle-like inequalities.

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Zhi-Xiang Jin, Xianqing Li-Jost, Shao-Ming Fei. 2018-11-20. Triangle-like inequalities related to coherence and entanglement negativity. https://doi.org/10.1007/s11128-018-2121-5

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