Characterizing High-Quality High-Dimensional Quantum Key Distribution by State Mapping Between Different Degrees of Freedom

Abstract

Quantum key distribution (QKD) guarantees the secure communication between legitimate parties with quantum mechanics. High-dimensional QKD (HDQKD) not only increases the secret key rate but also tolerates higher quantum bit error rate (QBER). Many HDQKD experiments have been realized by utilizing orbital-angular-momentum (OAM) photons as the degree of freedom (DOF) of OAM of the photon is a prospective resource for HD quantum information. In this work we proposed and characterized that a high-quality HDQKD based on polarization-OAM hybrid states can be realized by utilizing state mapping between different DOFs. Both the preparation and measurement procedures of the proof-of-principle verification experiment are simple and stable. Our experiment verified that (0.60 ± 0.06)% QBER and 1.849 ± 0.008 bits secret key rate per sifted signal can be achieved for a four-dimensional QKD with the weak coherent light source and decoy state method.

Vectorial light-matter interaction -- exploring spatially structured complex light fields

“…188 It is even possible to prepare the vector state of one photon by operations on its remote twin -a vectorial analogue to ghost imaging. 189 Quantum features of hybrid entanglement have been successfully employed for several protocols, including quantum key distribution 190 and quantum cryptography over an outdoor free-space link. 191…”

Reference-frame-independent quantum key distribution of wavelength division multiplexing with multiple quantum channels*

“…Unlike classical cryptography, security of quantum cryptography does not depend on mathematical complexity, but rather, is based on the fundamental principles of quantum physics. [1][2][3][4][5] However, during the implementation of a quantum key distribution (QKD) system, equipment defects lead to vulnerability of the security vulnerability of the QKD protocol. [6,7] To improve the security of a QKD system, many QKD protocols have been proposed.…”

Performance Analysis of Free-space Quantum Key Distribution Using Multiple Spatial Modes

“…The orbital angular momentum (OAM) bearing Laguerre-Gauss (LG) mode set [6] has emerged as a strong candidate for spatial multiplexing in classical and quantum communication systems. Their use in QKD was explored primarily for HD QKD [7][8][9][10], though other systems were also considered [11,12]. LG modes remain orthonormal while propagating through vacuum [4].…”