Increasing Quantum Communication Rates Using Hyperentangled Photonic States

TL;DR

This paper proposes a method to increase quantum communication rates by using hyperentangled photon states and multiplexing multiple degrees of freedom, enabling higher throughput in quantum networks.

Contribution

It introduces a novel multiplexing technique utilizing hyperentangled states to transmit multiple entangled pairs with a single photon, enhancing quantum communication efficiency.

Findings

Achieves higher transmission rates via hyperentanglement multiplexing.

Demonstrates generation of two entangled pairs from one photon.

Lays foundation for scalable quantum communication protocols.

Abstract

Quantum communication is based on the generation of quantum states and exploitation of quantum resources for communication protocols. Currently, photons are considered as the optimal carrier of information, because they enable long-distance transition with resilience to decoherence, and they are relatively easy to create and detect. Entanglement is a fundamental resource for quantum communication and information processing, and it is of particular importance for quantum repeaters [1]. Hyperentanglement [2], a state where parties are entangled with two or more degrees of freedom (DoFs), provides an important additional resource because it increases data rates and enhances error resilience. However, in photonics, the channel capacity, i.e. the ultimate throughput, is fundamentally limited when dealing with linear elements. We propose a technique for achieving higher transmission rates for quantum communication by using hyperentangled states, based on multiplexing multiple DoFs on a single photon, transmitting the photon, and eventually demultiplexing the DoFs to different photons at the destination, using a Bell state measurement. Following our scheme, one can generate two entangled qubit pairs by sending only a single photon. The proposed transmission scheme lays the groundwork for novel quantum communication protocols with higher transmission rate and refined control over scalable quantum technologies.