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Updated: Feb 23, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
The Experimental Demonstration of High Efficiency Interaction-free Measurement for Quantum Counterfactual-like
Chao Liu1,2, Jinhong Liu2, Junxiang Zhang3,4
1Department of Physics, Zhejiang University, Hangzhou, 310027, P. R. China.
Abstract:
We present an interaction-free measurement with quantum Zeno effect and a high efficiency η = 74.6% ± 0.15%. As a proof-of-principle demonstration, this measurement can be used to implement a quantum counterfactual-like communication protocol. Instead of a single photon state, we use a coherent light as the input source and show that the output agrees with the proposed quantum counterfactual communication protocol according to Salih et al. Although the counterfactuality is not achieved due to the presence of a few photons in the public channel, we show that the signal light is nearly absent in the public channel, which exhibits a proof-of-principle quantum counterfactual-like property of communication.
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