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arXiv · 0710.0565

Quantum key distribution using a triggered quantum dot source emitting near 1.3 microns

P. M. Intallura·M. B. Ward·O. Z. Karimov·Z. L. Yuan·P. See·A. J. Shields·P. Atkinson·D. A. Ritchie
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Abstract

We report the distribution of a cryptographic key, secure from photon number splitting attacks, over 35 km of optical fiber using single photons from an InAs quantum dot emitting ~1.3 microns in a pillar microcavity. Using below GaAs-bandgap optical excitation, we demonstrate suppression of multiphoton emission to 10% of the Poissonian level without detector dark count subtraction. The source is incorporated into a phase encoded interferometric scheme implementing the BB84 protocol for key distribution over standard telecommunication optical fiber. We show a transmission distance advantage over that possible with (length-optimized) uniform intensity weak coherent pulses at 1310 nm in the same system.

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P. M. Intallura, M. B. Ward, O. Z. Karimov, Z. L. Yuan, P. See, A. J. Shields, P. Atkinson, D. A. Ritchie. 2007-10-02. Quantum key distribution using a triggered quantum dot source emitting near 1.3 microns. https://doi.org/10.1063/1.2799756

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