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arXiv · 1307.3468

One-way deficit of SU(2) invariant states

Yao-Kun Wang·Teng Ma·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

We calculate analytically the one-way deficit for systems consisting spin-$j$ and spin-${1}{2}$ subsystems with SU(2) symmetry. Comparing our results with the quantum discord of SU(2) invariant states, we show that the one-way deficit is equal to the quantum discord for half-integer $j$, and is larger than the quantum discord for integer $j$. Moreover, we also compare the one-way deficit with entanglement of formation. The quantum entanglement tends to zero as $j$ increases, while the one-way deficit can remain significantly large.

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Yao-Kun Wang, Teng Ma, Shao-Ming Fei, Zhi-Xi Wang. 2013-07-12. One-way deficit of SU(2) invariant states. https://doi.org/10.1016/s0034-4877(14)60038-0

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