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School of Physics
PHYS1902 Physics 1 (Advanced) – Semester 2, 2013
MODULE 3 OUTLINE: QUANTUM PHYSICS
Unit Description
This module is one of three comprising PHYS 1902 Physics 1 (Advanced). This document describes details of
this module and should be read in conjunction with the more general unit of study outline for PHYS 1902
Physics 1 (Advanced).
General goals of this module
Quantum mechanics has revolutionised our understanding of both electromagnetic radiation and matter and
has facilitated rapid progress in most branches of science and engineering. Devices such as transistors and
lasers, based on quantum mechanics, have had an enormous impact on modern technology. The general
goals of this module are:
•
to study the critical experiments that revealed the inadequacy of the classical physics of Newton and
Maxwell;
•
to demonstrate the particle-like properties of electromagnetic radiation and the wave-like properties of
matter;
•
to prepare a foundation for the study of quantum mechanics by introducing matter wave functions and the
equation they satisfy; and
•
to study the quantisation of energy states for bound systems and, in particular, the arrangement of
electrons in atoms and the effects of this quantisation on the emission and absorption of electromagnetic
radiation.
MODULE DEFINITION & OBJECTIVES – QUANTUM PHYSICS
There is no easy road to learning. Your marks will depend on the work that you do. You should read through
and understand the sections of the textbook specified below, and work through the specified examples. You
should attempt as many as possible of the recommended Questions, Exercises and Problems. Problem
solving skills can only be acquired by practice.
Chapter 36
DIFFRACTION
Text sections:
6
Text example:
5
Specific objectives - after studying this chapter you should be able to:
•
Explain how X-rays are diffracted by crystals and use the Bragg condition.
Chapter 38
PHOTONS: LIGHT WAVES BEHAVING AS PARTICLES
Text sections:
all
Text examples:
all
Specific objectives - after studying this chapter you should be able to:
•
Describe the photoelectric effect and its properties.
•
Describe the key features of the experiments used to establish these properties.
•
Explain why these properties are hard to understand using classical physics.
•
Explain Einstein’s hypothesis that light is composed of bundles of energy (light quanta or photons).
•
Explain and use Einstein’s theory for the photoelectric effect.
•
Calculate the energy and momentum of a photon in terms of its wavelength or frequency.
•
Convert between electron volts and joules.
•
Describe qualitatively how a continuous X-ray spectrum is generated and calculate its cut-off wavelength.
•
Describe the Compton experiment and use the equation for the Compton shift.
•
Discuss the assumptions in Compton’s theory (no derivation required) and the implications of the theory.
•
Describe how diffraction experiments reveal both the wave and the particle nature of light.
•
Discuss the probability and wave descriptions of light.
•
Describe quantitatively how the Heisenberg Uncertainty Principle limits the precision of photon
measurements.
PHYS1902 Module 3 Outline
1
Copyright © 2013, The University of Sydney
Chapter 39
PARTICLES BEHAVING AS WAVES
Text sections:
all except 4
Text examples:
all
Specific objectives - after studying this chapter you should be able to:
•
Explain and use the de Broglie relation between momentum and wavelength.
•
Describe the Davisson and Germer and the Thomson diffraction experiments and their physical
significance.
•
Describe how the Bohr model for the hydrogen atom leads to quantisation of energy and angular
momentum.
•
Explain how emission and absorption spectra for hydrogen are accounted for by the Bohr model
•
Describe the and use the equation for the energy levels of a hydrogen atom.
•
Explain what is meant by blackbody radiation and describe qualitatively the blackbody spectrum.
•
Discuss the assumptions in Planck’s theory of blackbody radiation.
•
Apply the Heisenberg Uncertainty Principle to particles and explain how the position-momentum and
energy-time uncertainty relations limit the precision of measurements for particles
•
Describe the two-slit interference experiment that reveals both the wave and the particle nature of
particles.
Chapter 40
QUANTUM MECHANICS
Text sections:
all except 5
Text examples:
1 to 7
Specific objectives - after studying this chapter you should be able to:
•
Define the time dependent wave function for a particle, the probability density function, and stationary
states.
•
Define the plane wave solution to the Schrodinger equation for a free particle.
•
Define a wave packet as a superposition of free particle plane waves.
•
Discuss the relationship between wave packets and the Uncertainty Principle.
•
Use the Schrodinger equation to determine the wave functions and energy levels for the stationary states
of a particle in simple one-dimensional potentials involving locally constant values of the potential.
•
Describe how confinement of a matter wave leads to discrete (i.e. quantised) energy levels.
•
Describe the wave functions and probability density functions for a particle in the energy levels of an
infinite one-dimensional potential well.
•
Explain and use the equation for the energy levels of a particle in an infinite one-dimensional potential
well.
•
Describe qualitatively the differences between the energy levels, wave functions and probability density
functions for finite and infinite one-dimensional potential wells.
•
Describe qualitatively how a particle can tunnel through a potential barrier.
Chapter 41
ATOMIC STRUCTURE
Text sections:
41.3 to 41.7 (Exclude selection rules, spin orbit coupling, combining orbital and spin
angular momenta, screening, X-ray absorption spectra)
Text examples:
2, 3, 4, 5, 6, 10
Specific objectives - after studying this chapter you should be able to:
•
Describe the quantum numbers for a hydrogen atom and use spectroscopic notation.
•
Discuss qualitatively which features of the Bohr model are consistent with quantum mechanics.
•
Describe the Zeeman effect which indicates that orbital angular momentum is quantised.
•
Discuss the experimental evidence which indicates that electrons have quantised spin angular
momentum.
•
Explain how the Pauli Exclusion Principle determines the arrangement of the electrons in a multi-electron
atom.
•
Describe qualitatively how the characteristic X-ray spectrum is generated.
•
Describe the Moseley plot and explain its physical significance.
PHYS1902 Module 3 Outline
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Copyright © 2013, The University of Sydney