arXiv:0710.0565 · Applied Physics Letters

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

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

Published Oct 15, 2007• 80 citations

Abstract

We report the distribution of a cryptographic key, secure from photon number splitting attacks, over 35km of optical fiber using single photons from an InAs quantum dot emitting ∼1.3μm 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 1310nm in the same system.

DOI: 10.1063/1.2799756

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