Welcome to the Experimental Physics 6 – Solid-State Physics lecture, SS2025!

Exam

Written exam will take place on 29.07.25 at 12:00 in Großer Hörsaal

Lecture notes

last updated 30.04.2025 (lectures 1-12), work in progress, use with caution (and do let me know about any problems and errors)

Problem sheets

Bravais lattice and symmetry (due on 22.04)
Symmetry elements and symmetry groups (due on 29.04)
Crystal structures, x-ray diffraction (due on 6.05)
Reciprocal lattice, structure factor (due on 13.05)
Bonding in crystals, mechanical properties (due on 22.05)
Mechanical properties, dielectric properties (due on 29.05)

Moodle link for your solutions

There will be no Q&A sessions on Monday at 18:00 due to low participation. Ask your questions via e-mail.

Wednesday tutorials are discontunued for the same reason. Please, come on Monday or Friday.

The homework submission deadline will be on Thursday night from now on!

Lecture 11 (23.05.2025). Phonons and light

Unforeseen link between lattice vibrations and permittivity

infrared spectroscopy

greenhouse gases

Max Born and Edward Teller

Optical effects in solids by David Tanner is the best ever reading about light, crystals, and research applications of IR spectroscopy
Demonstration of an infrared spectrometer
Simple demonstration of the greenhouse gas effect, appreciate the atmospheric hurdles

Lecture 10 (22.05.2025). Phonons and sound

Lattice vibrations make noise and help in detecting earthquakes

ultrasound spectroscopy

Earth

Thomas Young

Vibrations of a diatomic chain visualized
Introduction into resonant ultrasound spectroscopy (free copy available here)
Seismic waves visualized, and basics of seismology

Lecture 9 (16.05.2025). Dielectric properties

lecture slides

Image by Ümit Kaya, LibreTexts (CC-BY-NC)

Polarization from orientation, and how to use your microwave oven

dielectric spectroscopy

water and ice

Lorentz and Lorenz

How much water is there in the Ocean? (on the importance of clustering in water)
Generation of microwaves, and why there are cold spots in a microwave oven

Lecture 8 (15.05.2025). Mechanical properties

lecture slides

Stress, strain, and how to tear things apart

high-pressure XRD, mechanical tests

iron alloys

Robert Hooke

Mechanical testing made simple, and a closer view of the tensile test
Design principle for auxetic materials (negative Poisson's ratio)

Lecture 7 (9.05.2025). Bonding in crystals

lecture slides

Close packings, holes, radii, and why size matters

calorimetry and Born-Haber cycle

tin

Linus Pauling

Lecture 6 (8.05.2025). Structure factor: all shades of diffraction

lecture slides

When extinctions are important, and how to catch light elements

neutron diffraction

solid hydrogen

DNA team

Dubious story of metallic hydrogen
Historical account of structural studies for macromolecules, including DNA
(resolving structures without finding atoms)

Lecture 5 (2.05.2025). Spaces of crystallography: Reciprocal lattice

lecture slides

Image by Ümil Kaya, LibreTexts (CC-BY-NC)

From real space to the reciprocal space; x-rays as the tool for space travel

synchrotron x-ray diffraction

aperiodic crystals

Max von Laue and Paul Ewald

On-line textbook by the Spanish Center for Crystallography offers one of the most intuitive (and animated!) descriptions of x-ray diffraction experiments (check chapters 5 and 6)
Crystal Structure Determination by Werner Massa is the best ever textbook on x-ray diffraction and crystal structure solution
Aperiodic crystals: Crystallographic excursion in superspace and Manifestations in biology

Lecture 4 (25.04.2025). Unpacking the crystal structure

lecture slides

Solid-state physics for dummies: a simple guide to crystal structures and their experimental probes

x-ray powder diffraction

diamond

William Bragg

VESTA and Open Crystallography Database, the two main tools for crystal structure visualization
Bilbao Crystallographic Server can answer most of your questions about space groups, Wyckoff positions, and symmetry operations
How to draw lattice planes in VESTA?
Video introduction into x-ray powder diffraction + a more technical one, should you want to see the real instrument

Lecture 3 (24.04.2025). Systematics of crystals: symmetry groups

lecture slides

Solid-state physics for nerds: Universal classification of crystals and their properties

circular dichroism

chiral crystals and molecules

Evgraf Fedorov

mindat.org, the largest collection of minerals and their shapes (try to guess crystal symmetries)
...or check the gallery of minerals, or simply visit Terra Mineralia in Freiberg
Behold and comprehend 230 space groups: real structure types and symmetry diagrams
Some examples of color-changing minerals: tanzanite, tourmaline, iolite
Demonstration of optical rotation and optical activity of sugars

Lecture 2 (17.04.2025). Symmetry as the guiding principle

lecture slides

What it means to be symmetric, and when wrong symmetry makes you aperiodic

polarimetry and birefringence

quasicrystals

Dan Shechtman

Faszination Kristalle und Symmetrie by Frank Hoffmann is a very fun reading about symmetry and crystallography; English version available too
The discovery of quasicrystals, or Shechtman against Pauling: part 1, part 2, part 3
Symmetry properties of tensors, or a simple reading that clarifies applications of Neumann's principle

Lecture 1 (10.04.2025). Bravais lattice, or how to pack a crystal?

lecture slides

We will learn how to build a lattice, and how large the kissing number can be

electron microscopy

photonic crystals

Paintings by M.C. Escher – an artistic exploration of periodic structures
Catalogue of lattices and kissing numbers – more than 160 000 entries in dimensions up to 40!
Animated view of the close packing + another, more practical one
Electron microscopy: a brief introduction
Photonic crystals: physics and manifestations in nature (advanced reading for a later time)

N.B. Lecture slides contain images from publications that may be licensed differently from the rest of this webpage.