Solid Physics Course

Lesson 1 • Nature and Classification of Solids

Distinguishes crystalline, polycrystalline, and amorphous solids by structural order. Sets the physical basis for all subsequent material analysis.

Lesson 2 • Interatomic Potentials and Cohesion

Introduces pair potentials, the Lennard-Jones model, and cohesive energy. Provides the quantitative link between bonding and equilibrium lattice spacing.

Lesson 3 • Scales and Units in Solid Physics

Reviews SI units, energy scales (eV, meV), and length scales (angstrom, nanometer). Ensures dimensional fluency for all quantitative work ahead.

Lesson 1 • Crystal Systems and Point Groups

Covers the seven crystal systems and 32 crystallographic point groups. Symmetry classification determines selection rules and tensor properties.

Lesson 2 • Common Crystal Structures

Analyses FCC, BCC, HCP, diamond cubic, and NaCl-type structures. Connects packing geometry to density and coordination number.

Lesson 3 • Bravais Lattices and Unit Cells

Defines the 14 Bravais lattices and primitive vs. conventional unit cells. Provides the geometric skeleton for describing all crystalline materials.

Lesson 4 • Space Groups and Crystal Symmetry

Extends point groups with translational symmetry to yield the 230 space groups. Provides the complete symmetry description needed for diffraction analysis.

Lesson 1 • Bragg's Law and Diffraction Conditions

Derives Bragg's law and the Laue condition as equivalent diffraction criteria. Connects geometric path-length arguments to reciprocal-space scattering vectors.

Lesson 2 • Neutron and Electron Diffraction

Contrasts neutron and electron probes with X-rays in terms of scattering cross-sections. Highlights applications to light-element location and thin-film analysis.

Lesson 3 • The Reciprocal Lattice

Constructs the reciprocal lattice from real-space vectors and defines reciprocal lattice vectors. This dual-space framework underlies all diffraction and band-structure theory.

Lesson 4 • Experimental X-Ray Diffraction Methods

Surveys powder diffraction, single-crystal methods, and synchrotron sources. Prepares students to interpret real diffractograms and assess data quality.

Lesson 1 • Classical Lattice Vibrations

Derives equations of motion for monatomic and diatomic chains using harmonic approximation. Establishes the dispersion relation concept central to phonon physics.

Lesson 2 • Phonons as Quantized Vibrations

Quantises lattice vibrations into phonons using the harmonic oscillator model. Introduces phonon occupation numbers and the Bose-Einstein distribution.

Lesson 3 • Thermal Conductivity and Anharmonicity

Introduces phonon-phonon scattering, Umklapp processes, and thermal resistance. Connects anharmonic effects to thermal expansion and conductivity limits.

Lesson 4 • Phonon Dispersion in 3D Crystals

Extends 1D models to three-dimensional crystals with multiple atoms per unit cell. Identifies acoustic and optical branches and their polarisations.

Lesson 1 • Quantum Free Electron Gas

Solves the Schrodinger equation for electrons in a box with periodic boundary conditions. Derives the density of states and Fermi energy at zero temperature.

Lesson 2 • Fermi-Dirac Statistics

Applies Fermi-Dirac distribution to electrons at finite temperature. Derives the Sommerfeld expansion and electronic heat capacity.

Lesson 3 • Electrical and Thermal Transport

Derives electrical conductivity, thermal conductivity, and the Wiedemann-Franz law quantum mechanically. Connects scattering mechanisms to resistivity temperature dependence.

Lesson 4 • Fermi Surface and Its Measurement

Defines the Fermi surface in k-space and its role in determining metal properties. Introduces de Haas-van Alphen oscillations as a direct measurement technique.

Lesson 1 • Bloch's Theorem and Crystal Momentum

Proves Bloch's theorem for electrons in a periodic potential and defines crystal momentum. Establishes the reduced zone scheme and band index notation.

Lesson 2 • Nearly Free Electron Model

Treats the periodic potential as a weak perturbation to the free electron gas. Shows how Bragg reflection opens band gaps at zone boundaries.

Lesson 3 • Tight-Binding Model

Constructs band structure from atomic orbital overlap integrals in the tight-binding approach. Applies the model to s-band and p-band formation in simple lattices.

Lesson 4 • Density Functional Theory Overview

Introduces DFT as the standard computational method for electronic structure. Covers the Hohenberg-Kohn theorems and Kohn-Sham equations at a conceptual level.

Lesson 1 • Intrinsic Semiconductor Carrier Statistics

Derives electron and hole concentrations in intrinsic semiconductors using Fermi-Dirac statistics. Establishes the mass-action law and intrinsic carrier density.

Lesson 2 • p-n Junction Physics

Analyses the built-in potential, depletion region, and I-V characteristics of a p-n junction. Derives the ideal diode equation from minority carrier injection.

Lesson 3 • Semiconductor Devices and Applications

Extends p-n junction physics to bipolar transistors, MOSFETs, and photodetectors. Connects device operation to band diagrams and carrier profiles.

Lesson 4 • Doping and Extrinsic Semiconductors

Analyses donor and acceptor impurity levels and their effect on carrier concentration. Covers compensation, freeze-out, and exhaustion regimes.

Lesson 1 • BCS Theory and Ginzburg-Landau Framework

Presents Cooper pair formation, the BCS gap equation, and the energy gap. Introduces the Ginzburg-Landau order parameter and coherence length.

Lesson 2 • Ferromagnetism and Exchange Interaction

Explains spontaneous magnetisation via the Heisenberg exchange interaction and mean-field theory. Derives the Curie-Weiss law and Curie temperature.

Lesson 3 • Antiferromagnetism and Ferrimagnetism

Extends exchange theory to antiparallel spin arrangements and mixed sublattice systems. Introduces the Néel temperature and spin-wave excitations.

Lesson 4 • Diamagnetism and Paramagnetism

Derives Langevin diamagnetism and Curie paramagnetism from atomic magnetic moments. Introduces Pauli paramagnetism as the free-electron contribution.