Efficient and low-noise single-photon detection in 1550 nm communication band by frequency upconversion in periodically poled LiNbO3 waveguides.
We demonstrate 1500 nm band single-photon detection with low dark-count noise and a potentially high efficiency, which may allow long distance and high-bit-rate quantum key distribution. By developing frequency upconversion devices based on periodically poled lithium niobate waveguides, which are specifically designed to use a pump wavelength longer than that of communication-band photons, we completely eliminate the dark-count noise caused by parasitic nonlinear processes in the waveguide. We observed an internal conversion efficiency as high as 40% and demonstrated scaling down to the single photon level while maintaining a background dark-count rate of 10(2)s(-1).
Kamada
H
H
NTT Basic Research Laboratories, NTT Corporation, Kanagawa, Japan. leroi@will.brl.ntt.co.jp
Asobe
M
M
Honjo
T
T
Takesue
H
H
Tokura
Y
Y
Nishida
Y
Y
Tadanaga
O
O
Miyazawa
H
H