Measurement-device-independent quantum key distribution with classical Bob and no joint measurement

TL;DR

This paper introduces a simplified measurement-device-independent quantum key distribution protocol where Bob's operations are purely classical and no joint measurements are needed, reducing technical complexity.

Contribution

The proposed protocol eliminates the need for joint measurements and quantum operations on Bob's side, simplifying implementation while maintaining security.

Findings

Protocol requires only individual measurements

Bob's operations are entirely classical

Lower technical implementation requirements

Abstract

Measurement-device-independent quantum key distribution (MDI-QKD) provides a method for secret communication whose security does not rely on trusted measurement devices. In all existing MDI-QKD protocols, the participant Charlie has to perform the Bell state measurement or other joint measurements. Here we propose an MDI-QKD protocol which requires individual measurements only. Meanwhile, all operations of the receiver Bob are classical, without the need for preparing and measuring quantum systems. Thus the implementation of the protocol has a lower technical requirement on Bob and Charlie.