Efficient verification of entangled continuous-variable quantum states
with local measurements
- URL: http://arxiv.org/abs/2103.16275v2
- Date: Tue, 12 Oct 2021 02:07:14 GMT
- Title: Efficient verification of entangled continuous-variable quantum states
with local measurements
- Authors: Ye-Chao Liu, Jiangwei Shang, Xiangdong Zhang
- Abstract summary: We establish a systematic framework for verifying entangled continuous-variable quantum states by employing local measurements only.
Our protocol is able to achieve the unconditionally high verification efficiency which is quadratically better than quantum tomography.
- Score: 0.9825966924601679
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Continuous-variable quantum states are of particular importance in various
quantum information processing tasks including quantum communication and
quantum sensing. However, a bottleneck has emerged with the fast increasing in
size of the quantum systems which severely hinders their efficient
characterization. In this work, we establish a systematic framework for
verifying entangled continuous-variable quantum states by employing local
measurements only. Our protocol is able to achieve the unconditionally high
verification efficiency which is quadratically better than quantum tomography
as well as other nontomographic methods. Specifically, we demonstrate the power
of our protocol by showing the efficient verification of entangled two-mode and
multimode coherent states with local measurements.
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