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The Classical Hall Effect Pauli Paramagnetism Landau Quantization The Aharonov-Bohm Phase Cyclotron Resonance The Quantum Hall Effect. Section 1.7: Magnetic Properties of a Free Electron Fermi Gas. A Free Electron in a Magnetic Field. neglect spin. : vector potential.
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The Classical Hall Effect Pauli Paramagnetism Landau Quantization The Aharonov-Bohm Phase Cyclotron Resonance The Quantum Hall Effect Section 1.7: Magnetic Properties of a Free Electron Fermi Gas
A Free Electron in a Magnetic Field neglect spin : vector potential Different ways to solve this problem: • Classical mechanics • 1a) Newtonian formalism • 1b) Hamiltonian formalism • Quantum mechanics • 2a) Wavefunction formalism • 2b) Operator formalism
A Free Electron in a Magnetic Field Classical mechanics (newtonian formalism) ( in this section) Cyclotron (spiral) motion
A Free Electron in a Magnetic Field Classical mechanics (hamiltonian formalism) canonical momemtum kinematic momemtum Fields & potentials: Gauge transformation nothing changes
A Free Electron in a Magnetic Field Classical mechanics (hamiltonian formalism) Landau gauge This is independent of y & z cyclic coordinates py and pz are constants of motion EOM: Same results as newtonian Relative coordinates
Simple Harmonic Oscillator : parabolic
A Free Electron in a Magnetic Field Q.M. Landau levels Landau-Peierls substitution : SHO!! Landau gauge
Density of States in a Magnetic Field Landau ladder 4 3 2 : cyclotron energy … 1 n = 0 1 2 3 4 5 n = 0 … DOS DOS Energy Energy 2D system + B 0D system 3D system + B 1D system
Operator Algebra for Landau Levels : Hamiltonian operator Raising & lowering operators for LL