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arXiv · 2004.07729

Estimating quantum coherence by noncommutativity of any observable and its incoherent part

Tanaya Ray·Ahana Ghoshal·Arun Kumar Pati·Ujjwal Sen
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Abstract

We establish a lower bound on the quantum coherence of an arbitrary quantum state in arbitrary dimension, using a noncommutativity estimator of an arbitrary observable of sub-unit norm, where the estimator is the commutator of the observable and its incoherent or classical part. The relation provides a direct method of obtaining an estimate of the quantum coherence of an arbitrary quantum state, without resorting to quantum state tomography or the existing witness operators.

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Tanaya Ray, Ahana Ghoshal, Arun Kumar Pati, Ujjwal Sen. 2020-04-16. Estimating quantum coherence by noncommutativity of any observable and its incoherent part. https://doi.org/10.1103/physreva.105.062423

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