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arXiv · 2206.02844

Uncertainty Relation for Non-Hermitian Systems

Namrata Shukla·Ranjan Modak·Bhabani Prasad Mandal
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Abstract

We construct uncertainty relation for arbitrary finite dimensional PT invariant non-Hermitian quantum systems within a special inner product framework. This construction is led by good observables which are a more general class of operators. We show that the cumulative gain in the quantum Fisher information when measuring two good observables for such non-Hermitian systems is way better than their Hermitian counterpart. Minimum uncertainty states being the best candidates for this gain near the exceptional point supports the intelligent or simultaneous non-Hermitian quantum sensors.

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Namrata Shukla, Ranjan Modak, Bhabani Prasad Mandal. 2022-06-06. Uncertainty Relation for Non-Hermitian Systems. https://doi.org/10.1103/physreva.107.042201

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