Nanjing University of Posts and Telecommunicatins

Chunhui Zhang

Qin Wang

Jian Li

Jingyang Liu

Huajian Ding

Qingqing Jiang

The present invention relates to the field of quantum communication, especially a quantum key distribution device that can be configured with multiple protocols. It uses the simplified Faraday-Michelson interference ring in combination with the intensity modulator to perform timestamp encoding in a chopping manner. The phase modulation is completed with a Sagnac ring device composed of a single-polarization phase modulator, a polarization beam splitter and a Faraday rotator, so as to achieve the purpose of composite encoding and decoding, thus realizing a quantum key distribution device which can be configured with multiple protocols and multiple decoy state schemes. This device can be compatible with multiple protocols including BB84 protocol, the reference frame-independent protocol, the six-state protocol and SARG protocol and is characterized with polarization-independent phase modulation and low system complexity.

Quantum key distribution device capable of being configured with multiple protocols

A Quantum Digital Signature (QDS)-based mail system and a transceiving method are provided. The system is a three-layer structure formed by a physical layer, a key layer, and an application layer. The physical layer is a key generation terminal and is used to generate a key string for signature in real time; the key layer is used to store the key string generated by the physical layer and provide a required key to the upper layer, namely, the application layer when required; and the application layer is a transceiving software part in the mail system, and is used to extract keys generated by the physical layer from the key layer so as to encrypt information to be sent. The mail transceiving method comprises: a quantum key distribution (QKD) phase, a mail signature phase, and a signature verification phase.

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Jiangsu, China

Chunhui Zhang