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arXiv · 1708.03090

Complementarity Relation for Coherence and Disturbance

Gautam Sharma·Arun Kumar Pati
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Abstract

Quantum measurements necessarily disturb the state of physical system. Once we perform a complete measurement, the system undergoes decoherence and loses its coherence. If there is no disturbance, the state retains all of its coherence. It is therefore natural to ask if there is trade-off between disturbance caused to a state and its coherence. We present a coherence disturbance complementarity relation using the relative entropy of coherence. For bipartite states we prove a complementarity relation between the quantum coherence, entanglement and disturbance. Similar relation also holds for quantum coherence, quantum discord and disturbance for a bipartite state. We illustrate the trade-off between the coherence and the disturbance for single qubit state for various quantum channels.

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Gautam Sharma, Arun Kumar Pati. 2017-08-10. Complementarity Relation for Coherence and Disturbance. https://doi.org/10.1103/physreva.97.062308

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