1. Topological Phase transitions and Topological phases of matter
by Reichmann Alexander

2. Overview Phase transitions Topology Quantum Hall effect
Superconductivity
Applications

3. Phase transition
Different propteries of materials originate from the different ways in which the atoms are organized
Organizations of atoms are called „orders“
Landau symmetry-breaking theory

4. Topology
Topology is a branch of mathematics that describes properties that only change step-wise (in whole numbers).
Example of a topological invariant: number of holes

5. Superconductivity
Zero electrical resistance below cricital temperature
Above Tc: vortices and antivorices are plentiful and spins are disordered.
Below Tc: Vortex-Antivortex pairs are formed below critical temperature

7. QM Hall effect Classical: QM:
Induced voltage in a Conductor is confined
Current carrying conductor to two dimensions and
Exposed to a magnetic field is cooled to near 0K

8. Applications: Stanene
Tin atoms arranged in a
single hexagonal layer
Predicted to be a
2D topological insulator
Superconductivity at room
temperature on its edges