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arXiv · 2108.00221

Experimental demonstration of optimal probabilistic enhancement of quantum coherence

Robert Stárek·Michal Mičuda·Michal Kolář·Radim Filip·Jaromír Fiurášek
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Abstract

We theoretically and experimentally investigate conditional enhancement of overall coherence of quantum states by probabilistic quantum operations that apply to the input state a quantum filter diagonal in the basis of incoherent states. We identify the optimal filters that for a given probability of successful filtering maximize the output coherence. We verify the performance of the studied quantum filters in a proof-of-principle experiment with linear optics, where a pair of two-level quantum systems is represented by polarization states of two photons. We comprehensively characterize the implemented two-qubit linear optical quantum filters by full quantum process tomography and we experimentally observe the optimal quantum coherence enhancement by quantum filtering.

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Robert Stárek, Michal Mičuda, Michal Kolář, Radim Filip, Jaromír Fiurášek. 2021-07-31. Experimental demonstration of optimal probabilistic enhancement of quantum coherence. https://doi.org/10.1088/2058-9565%2Fac10ef

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