Day 1

Periodic boundary conditions

Periodic boundary conditions are critical for describing electrons moving through in a finite sized system. They are also used in some favorite video games: Asteroids computer game - https://www.youtube.com/watch?v=WYSupJ5r2zo

Phenomenological models

Phenomenological models are often used in solid state physics. It impossible to start from the fundamental principles of QM and predict how Avagadro's number of electrons will behave. Phenomenological models express mathematically the results of observed phenomena and don't contradict known fundamental principles.

Impact of Solid State Physics on Technology

Integrated circuitsSilicon, SiOx, HfOx, other dielectrics
Solar cellsSilicon
LEDs and LasersInGaAs, AlGaN …
Magnetic storageFerromagnets
Sensors (CCDs, read heads, strain guages…)Silicon, nanostructures, ferroelectrics
Controlling lightFerroelectric, birefringent etc.
High power transistors (eg. electric motors)Silicon
Control of small motionPiezoelectrics
High freq electronics (cell phone transmitter chip)GaAs, Surface acoustic waves
Quantum Devices (coherent wavelike electrons, spin of electron)Nanostructures
SuperconductorsMetals, Ceramics
Transparent conductorsIndium Tin Oxide (In2O3)0.9(SnO2)0.1, graphene, carbon nanotubes

Metals form crystal grains

Pure gallium. Even in metal grain size was 100 nm, electrons would pass 300 atoms at a time that are perfect arranged in a periodic structure.

Imagine going into a building that open rooms arranged in a periodic structure…

How many electrons per atom will Al or K contribute to the sea?