285220 Quantum Computing (V) (SoSe 2024)

This course provides an introduction to the field of Quantum Computing and Quantum Information Theory.

Quantum computation, and more generally quantum information, are emerging and fast-progressing fields of science.
Quantum computers are made of quantum bits (“qubits”) and exploit properties inherent to quantum mechanics, such as superposition and entanglement. While such computers have the potential to enable secure communication and cryptography, and to efficiently simulate the structure and dynamics of quantum many-body systems, their physical realisation necessitates to isolate the computer from its environment, which is a huge technical challenge.

In the first part of the course we will cover topics involving “ideal” quantum computers, that are governed by quantum mechanics of isolated systems. This includes notions for the description of one- and multi-qubits systems, and concept of quantum information such as entanglement. We will study some important examples of quantum algorithms, such as the Shor and Grover algorithms, as well as notions of quantum circuits and quantum computational complexity. Finally we will investigate how to simulate physical quantum many-body systems with quantum computers.

In the second part of the course we will turn to quantum computing based on “real” quantum computers, which are imperfect and subject to noise due to interaction with their environment. After introducing the laws of quantum mechanics for open systems and related concepts of quantum information, we will discuss quantum error correction and fault-tolerant quantum computing, which aim at mitigating the defects of these imperfect quantum computers.

The tutorials will include “pen-and-paper“ problems as well as implementations of quantum algorithms that will be executed on simulated and real quantum computers.