dorsal/arxiv
View SchemaDifferential phase shift quantum key distribution experiment over 105 km fibre
| Authors | H. Takesue, E. Diamanti, T. Honjo, C. Langrock, M. M. Fejer, K. Inoue, Y. Yamamoto |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0507110 |
| URL | https://arxiv.org/abs/quant-ph/0507110 |
| DOI | 10.1088/1367-2630/7/1/232 |
| Journal | New J. Phys. 7, 232 (2005). |
Abstract
Since several papers appeared in 2000, the quantum key distribution (QKD) community has been well aware that photon number splitting (PNS) attack by Eve severely limits the secure key distribution distance in BB84 QKD systems with Poissonian photon sources. In attempts to solve this problem, entanglement-based QKD, single-photon based QKD, and entanglement swapping-based QKD, have been studied in recent years. However, there are many technological difficulties that must be overcome before these schemes can become practical systems. Here we report a very simple QKD system, in which secure keys were generated over >100 km fibre for the first time. We used an alternative protocol of differential phase shift keying (DPSK) but with a Poissonian source. We analysed the security of the DPSK protocol and showed that it is robust even against hybrid attacks including collective PNS attack over consecutive pulses, intercept-and-resend (I-R) attack and beamsplitting (BS) attack, because of the non-deterministic collapse of a wavefunction in a quantum measurement. To implement this protocol, we developed a new detector for the 1.5 um band based on frequency up-conversion in a periodically poled lithium niobate (PPLN) waveguide followed by a Si avalanche photodiode (APD). The use of the new detectors increased the sifted key generation rate up to > 1 Mbit/s over 30 km fibre, which is two orders of magnitude larger than the previous record.
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"abstract": "Since several papers appeared in 2000, the quantum key distribution (QKD)\ncommunity has been well aware that photon number splitting (PNS) attack by Eve\nseverely limits the secure key distribution distance in BB84 QKD systems with\nPoissonian photon sources. In attempts to solve this problem,\nentanglement-based QKD, single-photon based QKD, and entanglement\nswapping-based QKD, have been studied in recent years. However, there are many\ntechnological difficulties that must be overcome before these schemes can\nbecome practical systems. Here we report a very simple QKD system, in which\nsecure keys were generated over \u003e100 km fibre for the first time. We used an\nalternative protocol of differential phase shift keying (DPSK) but with a\nPoissonian source. We analysed the security of the DPSK protocol and showed\nthat it is robust even against hybrid attacks including collective PNS attack\nover consecutive pulses, intercept-and-resend (I-R) attack and beamsplitting\n(BS) attack, because of the non-deterministic collapse of a wavefunction in a\nquantum measurement. To implement this protocol, we developed a new detector\nfor the 1.5 um band based on frequency up-conversion in a periodically poled\nlithium niobate (PPLN) waveguide followed by a Si avalanche photodiode (APD).\nThe use of the new detectors increased the sifted key generation rate up to \u003e 1\nMbit/s over 30 km fibre, which is two orders of magnitude larger than the\nprevious record.",
"arxiv_id": "quant-ph/0507110",
"authors": [
"H. Takesue",
"E. Diamanti",
"T. Honjo",
"C. Langrock",
"M. M. Fejer",
"K. Inoue",
"Y. Yamamoto"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/1367-2630/7/1/232",
"journal_ref": "New J. Phys. 7, 232 (2005).",
"title": "Differential phase shift quantum key distribution experiment over 105 km fibre",
"url": "https://arxiv.org/abs/quant-ph/0507110"
},
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