TQM Lectures 2022

These are the slides from Michaelmas 2022. If you want a nice printable version for saving as a PDF, you can use e.g. austen.uk/lectures/many-body-wavefunctions/?print-pdf#/

If you ever want access to the $\LaTeX$ for the mathematical expressions, right click and select Show Math As > TeX Commands

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Lectures

  • Take place in the Small Lecture Theatre at the Cavendish Laboratory from 09.30-11.00 on Tuesdays and Thursdays.

Synopsis

  • Many Body Wavefunctions

    Product States. Fermi gas. Density, density matrix, and pair distribution.

  • Quantum Hall Effect

    Landau levels. Laughlin wavefunction. Fractional charge, Fractional statistics.

  • The Elastic Chain

    Quantizing a chain. Ground state displacement fluctuations. statistics.

  • Spin Models

    Heisenberg model. Heisenberg chain. Magnons. Antiferromagnets. Symmetry breaking. Spin wave theory.

  • A is for Annihilation

    Product states and occupation numbers. Creation and annihilation operators. The case of fermions. Representation of operators.

  • B is for Bunching

    Density correlations. Hanbury Brown and Twiss effect. Hartree–Fock theory.

  • Lattice Models

    Tight binding models. Hubbard models and the Mott transition. Superexchange.

  • Bose Gas

    Gross–Pitaevskii approximation. Superfluidity. Bogoliubov theory.

  • Fermi Gas

    Interactions described by perturbation theory. Quasiparticles. Landau Fermi liquid.

  • Superconductivity

    Cooper’s problem. BCS theory. The BCS-BEC crossover.

  • Response and Correlation

    Response functions. Structure factor. Dielectric function. Sum rules.

Course materials

Some books that you may find useful

Past exam papers (with solutions)

2017

2018

2019

2020

2021

2022

Discuss

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