Quantum cryptography device and method
US6438234B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1999 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Mar 5, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/0852
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method for communicating a key between two stations using an interferometric system for quantum cryptography. The method includes sending at least two light pulses over a quantum channel and detecting the interference created by the light pulses. The interfering pulses traverse the same arms of an interferometer but in a different sequence such that the pulses are delayed when traversing a quantum channel. The pulses are reflected by Faraday mirrors at the ends of the quantum channel so as to cancel any polarization effects. Because the interfering pulses traverse the same arms of an interferometer, there is no need to align or balance between multiple arms of an interferometer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.