Towards a distributed quantum computing ecosystem

Abstract

The Quantum Internet, by enabling quantum communications among remote quantum nodes, is a network capable of supporting functionalities with no direct counterpart in the classical world. Indeed, with the network and communications functionalities provided by the Quantum Internet, remote quantum devices can communicate and cooperate for solving challenging computational tasks by adopting a distributed computing approach. The aim of this study is to provide the reader with an overview about the main challenges and open problems arising in the design of a distributed quantum computing ecosystem. For this, the authors provide a survey, following a bottom-up approach, from a communications engineering perspective. They start by introducing the Quantum Internet as the fundamental underlying infrastructure of the distributed quantum computing ecosystem. Then they go further, by elaborating on a high-level system abstraction of the distributed quantum computing ecosystem. They describe such an abstraction through a set of logical layers. Thereby, they clarify dependencies among the aforementioned layers and, at the same time, a road-map emerges.

Fourier’s Quantum Information Processing

“…This protocol, as well as many others like those from quantum key distribution (QKD), with entangled [28,29] or polarized photons [30,31], and a relatively new family of protocols for quantum data security called quantum secure direct communication (QSDC) [32][33][34][35][36][37][38][39][40][41][42] are of main importance in a critical branch of quantum communications [24][25][26] called quantum cryptography [43,44]. Success of the latter has an obvious impact on a new version of the internet, named quantum internet [45][46][47][48][49][50][51][52][53][54][55][56][57][58]. In fact, a spectral analysis of this new network is of fundamental importance to increase its performance, given that the information exchange that will take place in quantum internet is based on signal traffic and processing, as well as on the use of entangled pairs in the transmitter, receiver, terrestrial quantum repeaters [59][60][61][62][63], and satellite quantum repeaters [64,65].…”

“…Based on the equivalences established in "Fourier's Quantum Information Processing" and "Quantum Entanglement, Teleportation, and Secret Sharing" of this work between QFT and quantum gates and circuits, as well as, QFT and quantum entanglement, respectively, it is possible to evaluate the evident projection of this study on the future quantum internet [45][46][47][48][49][50][51][52][53][54][55][56][57][58]. Specifically, and in relation to the leading literature on quantum internet [45][46][47][48][49][50][51][52][53], we can say that the equivalences presented in this work for gates of 1, 2 and more qubits are fundamental to improve the performance of the protocols used for entanglement swapping and quantum repeaters [45,47], as well as the entanglement analysis of qubits over longer links [45], quantum entanglement distillation and quantum teleportation [46], high and low-level quantum teleportation schemes [47], noisy and decoherence analysis and single-qubit error-detection using a single noisy Einstein-Podolsky-Rosen (EPR) pair [46,48], entanglement distribution via quantum switch [49], including analysis of quantum teleportation process in terms of density matrices [49]. Moreover, the understanding obtained from this work about the existing bridge between quantum Fourier transform (QFT) and the gates used in quantum information processing (QIP) will allow a better approach to quantum internet from the point of view of distributed computing [50,51].…”

“…Specifically, and in relation to the leading literature on quantum internet [45][46][47][48][49][50][51][52][53], we can say that the equivalences presented in this work for gates of 1, 2 and more qubits are fundamental to improve the performance of the protocols used for entanglement swapping and quantum repeaters [45,47], as well as the entanglement analysis of qubits over longer links [45], quantum entanglement distillation and quantum teleportation [46], high and low-level quantum teleportation schemes [47], noisy and decoherence analysis and single-qubit error-detection using a single noisy Einstein-Podolsky-Rosen (EPR) pair [46,48], entanglement distribution via quantum switch [49], including analysis of quantum teleportation process in terms of density matrices [49]. Moreover, the understanding obtained from this work about the existing bridge between quantum Fourier transform (QFT) and the gates used in quantum information processing (QIP) will allow a better approach to quantum internet from the point of view of distributed computing [50,51]. Finally, a better understanding of the spectral aspect behind quantum internet will lead to better distributed routing algorithms [52], and at the same time, it will result in the development of better cryptographic protocols, which will make it possible to mark the difference between the current internet and the future network of networks [53] (Fig.…”

Distributed Quantum Computing and Network Control for Accelerated VQE

“…Another form of distributed quantum computing is cloudbased quantum computing, with companies such as Amazon, Microsoft, IBM, and others each releasing their own versions of a cloud quantum computing service [17]. In this type of distributed quantum computing algorithm input from a client is sent to a server, the server executes the algorithm instructions and then sends the results back to the client.…”

Routing space exploration for scalable routing in the quantum Internet

“…In a quantum Internet scenario [20][21][22][23][24][25][26][27][28][29][30][31][43][44][45][46][47][48][49][50][51][52][53][55][56][57][58][59][60][61][78][79][80] , a primary task is to distribute quantum entanglement 54,81-98 from a source quantum node to a target quantum node through a set of intermediate quantum nodes called quantum repeaters 32,[99][100][101][102][103][104][105][106][107][108][109][110][111][112] . The entanglement distribution is realized in a step-by-step manner by the generation of short-distance entangled connections between quantum nodes.…”