US 11,989,080 B2
Quantum bit error rate minimization method
Nino Walenta, Bad Saarow (DE)
Assigned to ID QUANTIQUE SA, Carouge (CH)
Filed by ID QUANTIQUE SA, Carouge (CH)
Filed on Dec. 3, 2020, as Appl. No. 17/110,545.
Claims priority of application No. 19214208 (EP), filed on Dec. 6, 2019.
Prior Publication US 2021/0173733 A1, Jun. 10, 2021
Int. Cl. G06F 11/07 (2006.01); G01R 19/25 (2006.01); G06N 10/00 (2022.01); H04B 10/079 (2013.01); H04B 10/54 (2013.01); H04B 10/70 (2013.01); H04L 9/08 (2006.01)
CPC G06F 11/0754 (2013.01) [G01R 19/2503 (2013.01); G06F 11/0727 (2013.01); G06N 10/00 (2019.01); H04B 10/07953 (2013.01); H04B 10/54 (2013.01); H04B 10/70 (2013.01); H04L 9/0852 (2013.01); H04L 9/0858 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method to substantially minimize quantum bit error rate in a quantum key distribution system comprising:
i) determining an initial quantum bit error rate (QBER) for a quantum channel;
ii) using an existing intensity modulator bias voltage (VIM) to calculate a dynamic voltage step size δV that, if applied to VIM, will yield a minimum QBER;
iii) applying a voltage step of dynamic voltage step size in a first direction to the existing VIM to yield a stepped VIM;
iv) redetermining a QBER existing using the stepped VIM;
v) applying the voltage step in a second direction opposite the first direction to the existing VIM if and only if the redetermined QBER is greater than the initial QBER and leaving VIM unchanged if the redetermined QBER in less than the initial QBER.