Title |
Satellite-to-ground quantum key distribution
|
---|---|
Published in |
Nature, August 2017
|
DOI | 10.1038/nature23655 |
Pubmed ID | |
Authors |
Sheng-Kai Liao, Wen-Qi Cai, Wei-Yue Liu, Liang Zhang, Yang Li, Ji-Gang Ren, Juan Yin, Qi Shen, Yuan Cao, Zheng-Ping Li, Feng-Zhi Li, Xia-Wei Chen, Li-Hua Sun, Jian-Jun Jia, Jin-Cai Wu, Xiao-Jun Jiang, Jian-Feng Wang, Yong-Mei Huang, Qiang Wang, Yi-Lin Zhou, Lei Deng, Tao Xi, Lu Ma, Tai Hu, Qiang Zhang, Yu-Ao Chen, Nai-Le Liu, Xiang-Bin Wang, Zhen-Cai Zhu, Chao-Yang Lu, Rong Shu, Cheng-Zhi Peng, Jian-Yu Wang, Jian-Wei Pan |
Abstract |
Quantum key distribution (QKD) uses individual light quanta in quantum superposition states to guarantee unconditional communication security between distant parties. In practice, the achievable distance for QKD has been limited to a few hundred kilometres, owing to the channel loss of fibers or terrestrial free space that exponentially reduced the photon rate. Satellite-based QKD promises to establish a global-scale quantum network by exploiting the negligible photon loss and decoherence in the empty out space. Here we develop and launch a low-Earth-orbit satellite to implement decoy-state QKD with over kHz key rate from the satellite to ground over a distance of up to 1,200 km, which is up to 20 orders of magnitudes more efficient than that expected using an optical fiber (with 0.2 dB/km loss) of the same length. The establishment of a reliable and efficient space-to-ground link for faithful quantum state transmission paves the way to global-scale quantum networks. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
India | 13 | 16% |
United States | 8 | 10% |
United Kingdom | 5 | 6% |
Korea, Republic of | 3 | 4% |
France | 3 | 4% |
Japan | 2 | 2% |
Italy | 2 | 2% |
Spain | 2 | 2% |
Switzerland | 1 | 1% |
Other | 10 | 12% |
Unknown | 34 | 41% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 57 | 69% |
Scientists | 20 | 24% |
Science communicators (journalists, bloggers, editors) | 4 | 5% |
Practitioners (doctors, other healthcare professionals) | 2 | 2% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Unknown | 678 | 100% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Ph. D. Student | 180 | 27% |
Researcher | 90 | 13% |
Student > Master | 73 | 11% |
Student > Bachelor | 46 | 7% |
Student > Doctoral Student | 23 | 3% |
Other | 82 | 12% |
Unknown | 184 | 27% |
Readers by discipline | Count | As % |
---|---|---|
Physics and Astronomy | 297 | 44% |
Engineering | 109 | 16% |
Computer Science | 30 | 4% |
Materials Science | 10 | 1% |
Agricultural and Biological Sciences | 7 | 1% |
Other | 34 | 5% |
Unknown | 191 | 28% |