Prof. Dr. Walter Steurer "Solid State Symmetries and Structures"



9.05.2017 - 7.06.2017

 

The overarching goal of this course is to increase your familiarity with the concepts of symmetry and structure in general as well as with their applications in solid state physics and chemistry. You will learn how to use this concept in the course of materials characterization as well for understanding structure/properties relationships. Topics covered are basics of symmetry groups, structural order/disorder, principles of structure formation, periodic and aperiodic structures, building principles of structural and functional materials, structure/properties relationships of heterostructures such as photonic and phononic crystals, etc.

Course content:


  1. Fundamentals of symmetry
    • Introduction to the concept of symmetry; symmetry groups in nD (1 < n < 6); direct and reciprocal lattice.
    • Magnetic (black/white) and color symmetry groups; symmetry of solid-solid phase transformations.
    • Patterns and tilings as concepts underlying crystal structures.
  2. Structure and properties
    • Chemical bonding; structures of inorganic/metallic/organic/biological materials.
    • Tensorial physical properties; functional materials.
    • Beyond ideal crystals; real crystals.
  3. Higher-dimensional crystallography
    • Higher-dimensional crystallography.
    • Incommensurate structures; quasicrystals.
    • Entropically stabilized structures; high-entropy alloys.
  4. Experimental analysis of symmetry and structure
    • Introduction to methods of symmetry and structure analysis.
    • Diffraction methods.
    • Electron microscopic methods.
  5. Photonic and phononic crystals/exams
    • Structure/properties relationships for photonic crystals
    • Structure/properties relationships for phononic crystals
    • Oral exams (20 min each)



    Career Research Accomplishments of Walter Steurer


    In the focus of his research have been exciting fundamental questions about the self-organization of matter and structure/property relationships. However, also applied problems such as the development of improved coatings for gas-turbine blades have played a role. Studied materials range from intermetallic phases and ceramics to nanoparticles, colloids and metacrystals, from periodic structures with giant unit cells to incommensurately modulated structures and quasicrystals. The experimental conditions extend from low to high temperatures and pressures.

    WS has been from its very beginning one of the leading scientists contributing the structure analysis of quasicrystals, in particular decagonal quasicrystals, as well as of highly complex intermetallics.

    WS was the first studying experimentally and theoretically the influence of quasiperiodic order on the properties of phononic quasicrystals.

    Besides more than 200 scientific papers, WS published two comprehensive monographs: "Crystallography of Quasicrystals" (Springer 2009) and "Intermetallics - Structures, Properties and Statistics" (Oxford University Press 2016).