Six-State Quantum Key Distribution Using Photons with Orbital Angular Momentum

Federico M. Spedalieri

何业锋 He Yefeng, 杨红娟 Yang Hongjuan, 王登 Wang Deng +2 more

Ziwen Pan, Jiarui Cai, Chuan Xi Wang

Li Jun-Lin, Chuan Xi Wang

A new implementation of high-dimensional quantum key distribution (QKD) protocol is discussed. Using three mutual unbiased bases, we present a d-level six-state QKD protocol that exploits the orbital angular momentum with the spatial mode of the light beam. The protocol shows that the feature of a high capacity since keys are encoded using photon modes in d-level Hilbert space. The devices for state preparation and measurement are also discussed. This protocol has high security and the alignment of shared reference frames is not needed between sender and receiver.

Sandeep K. Goyal, Alpha Hamadou Ibrahim, Filippus Stefanus Roux +2 more

Abstract Using an experimental setup that simulates a turbulent atmosphere, we study the secret key rate for quantum key distribution (QKD) protocols in orbital angular momentum based free space quantum communication. The QKD protocols under consideration include the Ekert 91 protocol for different choices of mutually unbiased bases and the six-state protocol. We find that the secret key rate of these protocols decay to zero, roughly at the same scale where the entanglement of formation decays to zero.

Yuan Qian, Shengmei Zhao

How to improve the key distribution efficiency is key technique in quantum key distribution. An efficient quantum key distribution (QKD) protocol based on Orbital Angular Momentum (OAM) states in the d-dimension Hilbert space is presented in this paper. In the protocol, each photon carries log2d bits information, and the key distribution efficiency is improved greatly. In addition, the numerical simulation for this key distribution protocol are also given to show the availability of the protocol.