## Introduction to Quantum Networks

Module Number: EI71073

Duration: one semester

Occurence: winter semester and summer semester

Language: English

Number of ECTS: 5

## Staff

Professor in charge: Janis Nötzel

## Description of achievement and assessment methods

The module examination is carried out in the form of an oral examination (30 to max. 50 min). By answering questions and presenting a solution for a given problem, the students should prove that they are able to use the algorithms for entanglement assisted data transmission, which have been discussed in lectures and exercises. The ability to use QuNetSim is in addition demonstrated by completing programming tasks (every 2 weeks). The tasks can be completed in groups of up to 3 people. The tasks are graded and contribute 25% to the overall grade. In the exam, the ability to use QuNetSim is tested by querying the routines required to solve the task.

## (Recommended) requirements

Linear algebra (must-have), interest in mathematical modelling and programming with Python. Broadband Communication Networks and Grundlagen Rechnernetze und Verteilte Systeme

## Contents

The lecture introduces the participants to the topic of "quantum communication" within a framework they can experience on a daily basis. The processing of information by means of quantum technology is an active field of research in which industrial research has been conducted with increasing tendency during the last 20 years. However, industrial research is strongly focused on the development of quantum computers. Quantum communication has so far been perceived either as a new possibility for secure communication or as a pure basis for the networking of quantum computers. Recent results translated the earlier findings from quantum game theory and classical information theory to new communication models, showing that entangled particle pairs can also be used as a resource for coordinating interfering communication channels. These results are still of a highly theoretical nature. The TQSD group has therefore developed a Python-based network simulator, which is the first network simulator worldwide designed to simulate quantum effects on network layers 2, 3 and 4. The basics of using entanglement as a resource for coordination in communication networks will be taught to students by means of theoretical models and concrete tasks in data transmission via the network simulator

## Study goals

At the end of the course, participants will know the basics (mathematical representation of qubits, postulates) of quantum mechanics, the known fundamental effects of quantum information theory (superdense coding, teleportation) as well as protocols such as BB84, graph states, entanglement routing and entanglement assisted interference reduction. Participants will understand the relationship of these effects to the structure of current TCP/IP networks. They have learned to use the network simulator QuNetSim and can use the knowledge gained creatively to optimize TCP/IP networks by using quantum communication. Ideally, they will be able to analyse communication systems for a potentially beneficial application of quantum communication technology. They can use the acquired knowledge to attend advanced courses in quantum information theory, network engineering or the development and simulation of basic hardware for quantum communication.

## Teaching and learning methods

Development and presentation of the lecture contents on the blackboard. Consolidation of the lecture material by solving tasks and calculation examples in the exercises

## Media formats

The contents are presented by means of: Presentation on the blackboard. In the exercises Python is used to implement small algorithms. The algorithms show potential modifications in the TCP/IP stack that improve data transmission by using entanglement

## Literature

M. A. Nielsen, I. L. Chuang, "Quantum Computation and Quantum Information"

R. Van Meter, "Quantum Networks”