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ECE4060 Quantum Physics and Engineering

  

Lectures

 

Lecture notes

PART I: Introduction and Background

Handout 1

Introduction to the course.

Handout 2

A primer on classical wave phenomena. Wave propagation, wave equations, wave parameters, wave interference. 

Handout 3

An introduction to the historical foundations of quantum physics. Black body spectra, photoelectric effect, atomic spectra, De-Broglie hypothesis, Davisson, Germer, and Thomson experiments. The birth of wave mechanics.   

PART II: The Schrodinger Equation, the Wavefunction, and their Interpretation

Handout 4

Heruistic derivation of the Schrodinger equation, Max Born and the probabilistic interpretation of the wavefunction, introduction to measurement and wavefunction collapse, probability current.  

Handout 5 

Observables in quantum physics, mean values of observables.  

Handout 6          

Applications of the Schrodinger equation, time-independent form of the Schrodinger equation, energy eigenstates and energy eigenvalues, bound states in an infinite potential well, reflection and transmission of plane waves, barrier tunneling.   

PART III: Quantum Mechanics in the Dirac Notation

Handout 7

A math primer for quantum physics, vector spaces and Hilbert spaces, operators, inner and exterior products, adjoint operators, Hermitian operators, eigenvalues and eigenvectors, basis sets, orthonormal basis sets, representations, commutation relations, Hilbert space of square integrable functions, position basis and plane wave basis.  

Handout 8

Quantum physics in Dirac notation, bras and kets, Schrodinger equation in Dirac notation, observables, operators, and quantum states in the Dirac notation.  

Handout 9

Time evolution in quantum physics, stationary states, measurement and state collapse.  

Handout 10

Commutation relations, measurements, disturbances, and Heisenberg uncertainty relations in quantum mechanics, various forms of the Heisenberg uncertainty relation, simultaneous measurements of commuting and non-commuting observables.   

Handout 11

The formal postulates of quantum physics.

Handout 12

The finite potential well, bound states and unbound states.    

Handout 13

Simple harmonic oscillator (SHO) in classical and quantum physics, electromagnetic modes in an optical cavity, superconducting LC ciruits, quantization of a SHO, creation and destruction operators, operator algebra, energy eigenstates and eigenvalues, number states, quantization of an optical cavity mode and photons, quantization of a superconducting LC ciruit, introduction to vacuum fluctuations.   

Handout 14

Completely commuting set of observables (CSCOs), time-energy uncertainty relation in quantum physics, quasi-bound states and their lifetimes.

PART IV: Two-Level Systems (TLS), Qubits, Entanglement, and Decoherence

Handout 15

Spin in quantum physics, spin operators, quantum larmor precession, Zeeman splitting, the bit and the qubit, spin 1/2 qubit as a quantum two-level system (TLS), spin operators and Pauli matrices, spin qubit in a time-dependent magnetic field, spin Rabi oscillations, introduction to single-qubit quantum gates.  

Handout 16

Composite systems and quantum entanglement, joint Hilbert spaces and tensor products, entangled and unentangled states of bipartite systems, entangled states and the EPR paradox, absence of local realism in quantum physics.    

Handout 17

Quantum decoherence, entanglement, and the conscious observer, the double-split experiment, decoherence via entanglement, quantum which-path measurements by conscious and unconscious observers, the Schrodinger's cat paradox.    

Handout 18

Electron-photon interaction Hamiltonian, classical and quantum descriptions, electron in a finite potential well interacting with light as a two-level system (TLS), mapping to a spin Hamiltonian, Rabi Oscillations.

PART V: Perturbation Approaches in Quantum Physics

Handout 19

Time-dependent perturbation theory and Fermi's Golden Rule, optical transitions in energy bands, stimulated emission and absorption, spontaneous emission.  

 Handout 20

Time-independent perturbation theory, first order and second order changes in energy eigenstates and energy eigenvalues.

Handout 21

Time-independent perturbation approach using a finite basis expansion and sub-matrix diagonalization. 

PART VI: Quantum Information Processing, Quantum Gates, Quantum Circuits, and Quantum Computation

Handout 22

Interactions, entanglement, and two-qubit quantum gates. Coupled spins, coupled superconducting LC circuits, implementation of control-X, control-Y, and control-Z gates.   

Handout 23

Quantum bits and classical bits, single-qubit quantum gates (X,Y,Z,H,S, and T gates), two-qubit quantum gates (control-X, control-Y, control-Z, etc), linearity, unitarity, and reversability of quantum gates, quantum circuits, Bell circuit, swap circuit.  Quantum information processing, quantum memory search and Grover’s algorithm, quantum no-cloning theorem, quantum teleportation, quantum superdense coding, quantum parallelism in computations, the Deutsch algorithm, the Bernstein-Vazirani algorithm.

PART VII: Orbital and Spin Angular Momentum, Spin and Statistics, Fermions and Bosons, Identical Paticles and Many-Particle States, Hydrogen Atom, Energy Bands in Solids 

Handout 24

Orbital angular momentum, commutation relations, eigenvalues and eigenstates, spherical harmonics, spin angular momentum and its commutation relations, eigenvalues and eigenstates, Fermions and Bosons, spin-statistics theorem and Pauli's exclusion principle, spinor states and wavefunctions.  

Handout 25

Many-particle wavefunctions, spin-statistics theorem, Pauli's exclusion principle, identical particles.

Handout 26

Hydrogen atom problem in relative and center-of-mass coordinates, angular momentum and spherical harmonics, CSCO, eigenvalues and eigenstates, atomic orbitals. 

Handout 27

Electrons in periodic potentials, Bragg scattering, breakdown of perturbation theory, finite basis expansion, opening of energy gaps, introduction to energy bands in solids.  

 

 

 

 

 

 

 

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