231 research outputs found
Correlated photon-pair generation in reverse-proton-exchange PPLN waveguides with integrated mode demultiplexer at 10 GHz clock
We report 10-ps correlated photon pair generation in periodically-poled
reverse-proton-exchange lithium niobate waveguides with integrated mode
demultiplexer at a wavelength of 1.5-um and a clock of 10 GHz. Using
superconducting single photon detectors, we observed a coincidence to
accidental count ratio (CAR) as high as 4000. The developed photon-pair source
may find broad application in quantum information systems as well as quantum
entanglement experiments.Comment: 6 pages, 4 figures, presented at 2007 CLEO conferenc
Single-photon detection timing jitter in a visible light photon counter
Visible light photon counters (VLPCs) offer many attractive features as
photon detectors, such as high quantum efficiency and photon number resolution.
We report measurements of the single-photon timing jitter in a VLPC, a critical
performance factor in a time-correlated single-photon counting measurement, in
a fiber-coupled closed-cycle cryocooler. The measured timing jitter is 240 ps
full-width-at-half-maximum at a wavelength of 550 nm, with a dark count rate of
25 000 counts per second. The timing jitter increases modestly at longer
wavelengths to 300 ps at 1000 nm, and increases substantially at lower bias
voltages as the quantum efficiency is reduced
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