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arXiv · 0901.0525

Derivation of sensitivity of a Geiger mode APDs detector from a given efficiency for QKD experiments

Kiyotaka Hammura·David Williams
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Abstract

The detection sensitivity (DS) of the commercial single-photon-receiver based on InGaAs gate-mode avalanche photodiode is estimated. Instalment of a digital-blanking-system (DBS) to reduce dark current makes the difference between DS, which is an efficiency of the detector during its open-gate/active state, and the total/overall detection efficiency (DE). By numerical simulations, it is found that the average number of light-pulses, blanked by DBS, following a registered pulse is 0.333. DS is estimated at 0.216, which can be used for estimating DE for an arbitrary photon arriving rate and a gating frequency of the receiver.

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Kiyotaka Hammura, David Williams. 2009-01-05. Derivation of sensitivity of a Geiger mode APDs detector from a given efficiency for QKD experiments. https://doi.org/10.1088/1464-4258/11/5/054003

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