物理学报2016，Vol.65Issue(3)：030303-1-030303-6,6.DOI:10.7498/aps.65.030303
纠缠比特在不同噪声环境和信道下演化规律的实验研究∗
Evolutions of two-qubit entangled system in different noisy environments and channels
摘要
Abstract
Quantum information technology is mainly based on quantum entanglement. As an important coherent superposi-tion state, the coherence of quantum entanglement source is easily affected by environment and becomes fragile, which will lead to the failure of the quantum information processing. Thus, it is critical to reveal the evolutions of quantum entanglement source under different noisy environments and different noisy channels. Firstly, we experimentally prepare a high-fidelity two-bit entangled state by several technical methods. The fidelity observed for the state prepared in our experiment is 0.993 and the signal-to-noise ratio can reach up to 299. Then, we simulate the bit-flip noise and phase-shift noise (collective and non-collective) using the all-optical experimental setup. Finally, based on the entanglement qubit state, we experimentally study the evolutions of entanglement characteristic under different noisy environments and the single, double and mixed noisy channels. The experimental results show that for the same type of noise, the entanglement properties disappear fast when entangled qubit passes through dual channel noisy environment. The upper bounds of noise intensity to destroy the entanglement property are 0.25 and 0.26 for the single bit-flip noise and phase-shift noisy channels, respectively. The comparison between the two different kinds of noisy environments shows that the entan-glement properties disappear fast when entangled bit passes through non-collective environment. The upper bounds of noise intensity are 0.08 and 0.14 for non-collective bit-flip and phase-shift noise to destroy the entanglement property, while the noise intensities are 0.14 and 0.23 for collective bit-flip and phase-shift noise, respectively. For different kinds of noises, the results show that bit-flip noise is more likely to destroy the entanglement properties than the phase-shift. Our results have great significance for the theoretical and experimental studies of entanglement decoherence and have important application value for quantum information processing technology based on the nonlinear optical system.关键词
比特翻转噪声/相移噪声/量子通道/量子消相干Key words
bit-flip nosie/phase-shift noise/quantum channel/decoherence引用本文复制引用
曹连振,刘霞,赵加强,杨阳,李英德,王晓芹,逯怀新..纠缠比特在不同噪声环境和信道下演化规律的实验研究∗[J].物理学报,2016,65(3):030303-1-030303-6,6.基金项目
国家自然科学基金(批准号:11174224,11404246,11447225)、山东省自然科学基金(批准号：BS2015DX015)、山东省科技发展计划(批准号:2011YD01049,2013YD01016)和山东省高等学校科技计划(批准号：J13LJ54, J15LJ54)资助的课题.* Project supported by the National Natural Science Foundation of China (Grant Nos.11174224,11404246,11447225), the Natural Science Foundation of Shandong Province, China (Grant No. BS2015DX015), the Science and Technology Development Program of Shandong Province, China (Grant Nos.2011YD01049,2013YD01016), and the Higher School Science and Technology Program of Shandong Province, China (Grant Nos. J13LJ54, J15LJ54) （批准号:11174224,11404246,11447225）
