Experimental demonstration of entanglement delivery using a quantum network stack

Abstract

Scaling current quantum communication demonstrations to a large-scale quantum network will require not only advancements in quantum hardware capabilities, but also robust control of such devices to bridge the gap in user demand. Moreover, the abstraction of tasks and services offered by the quantum network should enable platform-independent applications to be executed without the knowledge of the underlying physical implementation. Here we experimentally demonstrate, using remote solid-state quantum network nodes, a link layer, and a physical layer protocol for entanglement-based quantum networks. The link layer abstracts the physical-layer entanglement attempts into a robust, platform-independent entanglement delivery service. The system is used to run full state tomography of the delivered entangled states, as well as preparation of a remote qubit state on a server by its client. Our results mark a clear transition from physics experiments to quantum communication systems, which will enable the development and testing of components of future quantum networks.

Reliable Quantum Communications Based on Asymmetry in Distillation and Coding

“…We report these comparisons for both the single link and network scenarios, varying the adopted [[n, k]] with (e g , e Z ) error correcting code. Due to implementation reasons, we focus our results on short quantum codes such as the [ [3,1]] and [ [5,1]] repetition codes, the 5-qubit code [35], the [ [11,1]] code able to correct up to 2 generic errors [36], and the [ [9,1]] and [ [13,1]] asymmetric codes [38]. In the following, we consider only the case where the initial state is a Werner one.…”

“…From the plot, we can observe some interesting behaviors. Firstly, we note that the simple and easy-to-implement [ [3,1]] repetition code [5,1]] w/ (eg = 1, eZ = 0) [ [3,1]] w/ (eg = 0, eZ = 1) [ [5,1]] w/ (eg = 0, eZ = 2) [ [11,1]] w/ (eg = 2, eZ = 0) [ [9,1]] w/ (eg = 1, eZ = 1) [ [13,1]] w/ (eg = 1, eZ = 2) FIGURE 9. Logical qubit error probability against the initial error probability ρ0 = 1 − F0 considering a single distillation step.…”

“…The evolution of the quantum Internet happens in symbiosis with classical communication and the existing Internet technology, leading to a number of interesting research challenges [1]- [3]. There are two principal types of applications for quantum communication: (a) enhancing already existing services such as quantum key distribution [4] or super-dense coding [5]; (b) enabling new services, such as distributed quantum computing [6]- [8] or remote processing of quantum sensing data [9], [10].…”

Analysis of multipartite entanglement distribution using a central quantum-network node

“…Assuming classical signals travel at the same speed of light (in fiber) as the photons used to generate entanglement, this time is exactly equal to t cl . t may be further limited by, among others, the rate at which entangled photons can be emitted and by classical overhead due to, e.g., synchronizing emission times [8,72,73]. In that case, t cl < t. In this paper, we focus on the case q link 1.…”

Cavity-Enhanced Single-Photon Emission from a Single Impurity-Bound Exciton in ZnSe

“…Single-photon sources are essential components of photonics-based quantum information processors, − quantum networks, − and photonic quantum simulators. − Among the various approaches to generating single photons, impurity-bound excitons in II–VI wide-bandgap semiconductors have emerged as a promising material platform for realizing efficient single-photon emission. − These emitters also possess a natural spin ground state that can act as a qubit, opening the possibility to realize efficient spin-photon interfaces. ,,, In addition, ZnSe quantum wells can be grown and isotopically purified to deplete the nuclear spin background, which should lead to a drastic increase in the spin dephasing times. However, fully harnessing the potential of these emitters for quantum applications requires methods to extract their photon emissions with high efficiency.…”