Systems and methods for measurement-device-independent quantum key distribution
US11888978B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2021 |
| Grant date | Jan 30, 2024 |
| Priority date | — |
| Expiry date | Mar 20, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/12
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A measurement-device-independent quantum key distribution (MDI-QKD) network includes a plurality of user nodes connected to untrusted relay node that performs Bell-state measurements on qubits transmitted by the user nodes. The relay node contains a calibration laser that serves as a wavelength reference for the user nodes. The output of the calibration laser is split into two wavelength-calibration signals, which are transmitted to a pair of user nodes via optical fiber. At each user node, a laser diode used to generate weak coherent pulses is injection-locked with the wavelength calibration-signal, thereby ensuring that the user nodes generate photonic qubits with the same wavelength. The embodiments may be implemented with any encoding scheme compatible with MDI-QKD, such as polarization encoding and time-bin phase-encoding. No auxiliary connections between the user nodes are needed, allowing the MDI-QKD network to be scaled up to many users.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.