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arXiv:2604.20149 · Physics Letters A

Average metric adjusted skew information of coherence under conical 2-designs generalized equiangular measurements

Baolong Cheng, Linlin Ye, Zhaoqi Wu

quant-phSubmitted Apr 22, 2026• Announced Apr 23, 2026• 0 citations
v1 · Apr 22, 2026v2 · Oct 2, 2026
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Abstract

Quantum coherence is an important quantum resource which plays a pivotal role in the field of quantum information. Based on metric adjusted skew information, we define a measure of quantum uncertainty to study average coherence under conical 2-designs generalized equiangular measurements, and prove the equivalence of this measure to the scaled average coherence based on metric adjusted skew information under a set of unitary groups, operator orthonormal bases, and mutually unbiased bases. We also derive two trade-off relations by this measure and solve a conjecture. Furthermore, we give two entanglement criteria by this measure and conical 2-designs generalized equiangular measurement, respectively, and illustrate the effectiveness of them by explicit examples.

Journal reference
Phys. Lett. A 2026, 595: 132087
DOI
10.1016/j.physleta.2026.132087
Comments
19 pages

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