Experimental Quantum Key Distribution with Decoy States
Abstract
To increase dramatically the distance and the secure key generation rate of quantum key distribution (QKD), the idea of quantum decoys—signals of different intensities—has recently been proposed. Here, we present the first experimental implementation of decoy state QKD. By making simple modifications to a commercial quantum key distribution system, we show that a secure key generation rate of 165 bit/s, which is 1/4 of the theoretical limit, can be obtained over 15 km of a telecommunication fiber. We also show that with the same experimental parameters, not even a single bit of secure key can be extracted with a non-decoy-state protocol. Compared to building single photon sources, decoy state QKD is a much simpler method for increasing the distance and key generation rate of unconditionally secure QKD.
- Publication:
-
Physical Review Letters
- Pub Date:
- February 2006
- DOI:
- 10.1103/PhysRevLett.96.070502
- arXiv:
- arXiv:quant-ph/0503192
- Bibcode:
- 2006PhRvL..96g0502Z
- Keywords:
-
- 03.67.Dd;
- 42.50.Dv;
- Quantum cryptography;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Quantum Physics
- E-Print:
- Revised Version, 4 pages, one figures, two-column format