Realistic ratedistance limit of continuousvariable quantum key distribution
Abstract
In this work, the ratedistance limit of continuous variable quantum key distribution is studied. We find that the excess noise generated on Bob's side and the method for calculating the excess noise restrict the ratedistance limit. Then, a realistic ratedistance limit is found. To break the realistic limit, a method for calculating the secret key rate using pure excess noise is proposed. The improvement in the ratedistance limit due to a higher reconciliation efficiency is analyzed. It is found that this improvement is dependent on the excess noise. From a finitesize analysis, the monotonicity of the Holevo bound versus the transmission efficiency is studied, and a tighter ratedistance limit is presented.
 Publication:

Optics Express
 Pub Date:
 April 2019
 DOI:
 10.1364/OE.27.013372
 arXiv:
 arXiv:1809.00755
 Bibcode:
 2019OExpr..2713372W
 Keywords:

 Quantum Physics
 EPrint:
 5 pages,5 figures