## Lectures: Winter Semester 2021-2022

The 2021-2022 winter semester runs from **October 1st 2021 - March 31st 2022**. Owing to COVID-19 pandemic restrictions, several courses will take place wholly or partly online. Lectures will run from October 11th-December 22nd and then January 5th-February 5th.

The online platform used by TU Dresden is called Opal. If you do not already have an Opal account, you can register for one here. Once you have access you will be able to view the course materials for at least some of the courses listed here.

**General lecture: Computational Tools for Quantum Many-Body Physics**

lecturer: | Prof. Jan Carl Budich | |

time: | Tuesdays 13:00-14:30, Wednesdays 14:50-16:20 starting October 12th | |

location: | REC/B214 (Tuesdays), REC/C118 (Wednesdays). Also broadcast via Zoom | |

content: | In this lecture, numerical tools for quantum many-body physics will be theoretically discussed and practically applied. We will cover mean-field theory, exact diagonalization, tensor network methods such as DMRG, and quantum Monte Carlo methods. The successful participant will be guided with accompanying exercises towards developing own source codes for solving basic quantum many-body problems using the aforementioned methods. |

**General lecture: Introduction to the Theory of Topological Materials**

lecturer: | Dmitry Efremov (IFW) | |

time: | Wednesdays 14:50-16:20; Fridays 13:00-14:30 | |

location: | REC/D16 | |

content: | The aim of this course of lectures is an elementary introduction to the foundations of the theory of topological insulators, topological superconductors and topological semimetals. We start with simple one-dimensional topological models, introduce the Berry phase and Chern invariants, and move on to “topological” phases in condensed media. We will discuss how the concept of topology helps us to understand the physical properties of topological materials such as polarization, topologically protected edge states, quantized transverse conductivity, and so on. |

**General lecture: Stochastic Processes: Classical and Quantum**

lecturer: | Prof. Walter Strunz | |

time: | Tuesdays 14:50-16:20; Thursdays 13:00-14:30 | |

location: | BZW/A120 (Thursdays), REC/C118 (Tuesdays) | |

content: | 1. Introduction 2. Open (quantum) systems 3. Stochastic processes, Kolmogorov Theorem, Markov processes 4. Langevin equation, stochastic differential equations (Ito, Stratonovich) 5. Fokker-Planck equation, (quantum) master equation 6. Path integrals: quantum and classical 7. Stochastic Schrödinger equations 8. Continuous measurement 9. Quantum Markov and non-Markovian processes. To clarify the information university website: this lecture course is in English. |

**General lecture: Chaos in higher-dimensional systems**

lecturer: | Prof. Dr. A. Bäcker (TUD) | |

time: | Mondays 11:10-12:40 , Tuesdays 09:20-10:50 | |

location: | BZW A120 Zellescher Weg 17 | |

content: | N-body problem; Hamiltonian systems, invariant objects (fixed points, periodic trajectories, invariant tori, and stable and unstable manifolds), nonlinear resonances, bifurcations, Arnold diffusion. Examples: coupled maps, Fermi-Pasta-Ulam-Tsingou problem, spin chains, ... |

**General lecture: Biological Hydrodynamics**

lecturer: | Dr. Benjamin Friedrich (TUD) | |

time: | Wednesdays 11:10-12:40 , Thursdays 14:50-16:20 | |

location: | MPI PKS Seminar Room 3 | |

content: | This class is divided in three parts and will cover hydrodynamics of passive fluids, hydrodynamics of active fluids, and biological pattern formation processes. We will review basics of continuum mechanics and equilibrium and non-equilibrium thermodynamics, linear response theory, Onsager Relations, and the derivation of hydrodynamic equations both from microscopic rules and from a phenomenological approach using broken symmetries and conservation laws. Topics for passive fluids include thin film fluids and the statics and dynamics of nematic liquid crystals. Topics for active fluids include active nematic or polar fluids and biological fluids. Moving beyond linear response we will discuss spatial chemical systems, bifurcation theory, and biological pattern formation. The class will end on coupled chemical and hydrodynamic pattern formation processes relevant for morphogenesis. |

**Special lecture: Theory of Open Quantum Systems applied to Molecular Aggregates**

lecturer: | Dr. A Eisfeld |

time: | Mondays 16:40-18:10 |

location: | MPI PKS or online. Contact lecturer to enrol. |

content: | - Molecular Hamiltonian - Born Oppenheimer approximation - Interaction with environment - Basics about open quantum systems - Redfield equation |

**Special lecture: Magnetism on the nanoscale**

lecturer: | Prof. B. Büchner, Dr. J. Dufouleur, Dr. T. Mühl | |

time: | Mondays 16:40-18:10 starting October 11th | |

location: | IFW D2E.27 | |

content: | The aim of this lecture is to give an insight into the exciting research in the field of magnetism and magnetic materials on the nanoscale. We will start with an introduction in the basics of (ferro)magnetism and magnetic materials with particular focus on magnetic anisotropy, domains and exchange bias and we will give an introduction to magnetic microscopy. Using this knowledge, superparamagnetism and molecular magnets will be discussed. In addition, we will cover aspects of spin transport phenomena such as giant and tunneling magneto resistance, including e.g.a discussion on spin transfer torque. |

**Special lecture: Optical spectroscopy of quantum matter**

lecturer: | Dr. Aliaksei Charnukha | |

time: | Wednesdays 16:40-18:10 | |

location: | REC/C118/U | |

content: | o Fundamentals of optical spectroscopy o Electromagnetic waves in vacuum and matter o Dielectric function and optical conductivity o Types of material response and their manifestations in optics o Sum rules and Kramers-Kronig relations o Optics of interfaces, surface modes o Screening and Lindhard response function o Modern experimental optical techniques |

**Special lecture: Few- to Many-Body Physics in Ultra-cold Gases**

lecturer: | Dr. P. Giannakeas | |

time: | Mondays 16:40-18:10. | |

location: | Zoom. Contact lecturer to enrol. | |

content: | Ultracold atoms is a vibrant field of atomic physics which emerged after the experimental observation of the first Bose-Einstein condensate in 1995. The reason for that relies on the fact that ultracold gaseous matter is highly controllable in an experimental environment. By means of external electromagnetic or optical fields atoms can be trapped to any potential or adjust their mutual interactions. In this specialized course, we will focus on the few- and many-body aspects of ultracold physics and in particular we will explore the few-to-many body regime. In a bottom-up approach, we will delve into underlying physical mechanisms that dictate or alter the properties of a many-body environment. |

**Special lecture: Dynamical Systems**

lecturer: | Prof. H. Kantz | |

time: | Mondays 11:10-12:40. | |

location: | SR3 MPI PKS or Zoom. Contact lecturer to enrol. Starts Nov 1st. | |

content: | nonlinear dynamics: fixed points and their bifurcations, classical chaos, continuous versus discrete time, attractors, invariant measure, fractal dimension, Lyapunov exponents, information theory, transient chaos |