Classical Capacity for a Continuous Variable Teleportation Channel

Qin Tao, Meisheng Zhao, Zhang Yong-De

The process of quantum teleportation can be considered as a quantum channel. The exact classical capacity of the continuous variable teleportation channel is presented and the channel fidelity is also derived.

Akira Furusawa, Harry J. Kimble

Akira Furusawa

Xinchao Ruan, Hang Zhang, Wenqi Peng +4 more

Quantum teleportation is one of the fundamental primitives of quantum cryptography. In order to achieve a wider range of high-capacity information transfer, we propose a free-space quantum teleportation (QT) protocol with orbital angular momentum (OAM) multiplexed continuous variable (CV) entangled states. The preparation of the entangled states is accomplished by the spontaneous four-wave mixing (SFWM) process occurring in a hot 85Rb vapor cell, and the mode selection for the Bell-state measurement is achieved by employing the balanced homodyne detection technique. The fidelity of teleporting EPR entangled states carrying different topological charges via a Kolmogorov-type atmospheric turbulence channel is derived, and the superiority of enhancing the system channel capacity via OAM multiplexing is demonstrated. Our work provides a feasible scheme to implement high-capacity quantum communication in atmospheric environments.

Alexander Semenovich Holevo, A A Kuznetsova

Abstract The present paper is devoted to investigation of the classical capacity of infinite-dimensional continuous variable quantum measurement channels. A number of usable conditions are introduced that enable us to apply previously obtained general results to specific models, in particular, to the multi-mode bosonic Gaussian measurement channels. An explicit formula for the classical capacity of the Gaussian measurement channel is obtained in this paper without assuming the global gauge symmetry, solely under certain ‘threshold condition’. The result is illustrated by the capacity computation for a one-mode squeezed-noise heterodyne measurement channel.

Liyun Hu, Zeyang Liao, Shengli Ma +1 more