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Keith P. Madden, PhD.
Ivy Tech Community College
South Bend, IN
Nanotechnology revolution is here!
◦ Transition from macroscopic to microscopic
systems.
◦ New materials and processes operating at
molecular size scale.
◦ The behavior of these systems is not well explained
using classical concepts.
Colloidal quantum dots
CdSe
10K
45Å
27Å
19Å
16Å
13Å
12Å
2.0
2.5
3.0
3.5
Energy (eV)
4.0
Absorbance
Luminescence
22Å
Mostly mechanical /thermal systems, with the
traditional development. My PHYS 101 topic
list:
1 Introduction, Technical Measurements,
Vectors, Translational Equilibrium, Friction
(Measurements)
2 Torques & Rotational Equilibrium (Equilibrium)
3 Uniformly Accelerated Motion & Projectile
Motion (Gravitational Acceleration)
4 Newton’s Second Law (Newton’s Second Law)
5 Work, Energy and Power
6 Impulse and Momentum
7 Uniform Circ. Motion (Centripetal Acceleration)
8 Rotation of Rigid Bodies (Density of Materials)
9 Elasticity (Hooke’s Law & Hysteresis)
10 Fluids (Fluid Flow)
11 Temperature & Expansion Quantity of Heat
12 Heat Transfer (Specific Heat)
13 Thermal Properties, Thermodynamics, &
Nanotechnology

When math is considered sufficient
Calculus, Systems of Linear Equations

After Physics 101 – 102, Classical Mechanics,
and Electricity and Magnetism

A long time to wait in a two-year program!

We need to show the inadequacies of classical
concepts – and the way past that problem.
Dr. Thomas Young (1802) – light is a wave
R.A. Millikan (1916) – light is a particle
1. The electrons were emitted
immediately - no time lag!
2. Increasing the intensity of the light
increased the number of
photoelectrons, but not their
maximum kinetic energy!
3. Red light will not cause the ejection
of electrons, no matter what the
intensity!
4. A weak violet light will eject only a
few electrons, but their maximum
kinetic energies are greater than those
for intense light of longer wavelengths!

The particle in a box
◦ Advantages: Mathematically simple
◦ Disadvantage: Correct solution to problem is not
completely plausible.
Wavefunction Amplitude
Wavefunction Amplitude
Squared



We have discrete energies for each state of the
particle.
We have discrete positions for the particle.
If the barriers are not infinite, we have a finite
probability of finding the particle outside the
box.
 What
kind of bowling alley is this??

The operators that are used to elucidate the
proton system are:
 S2 Total angular momentum squared
 Sz Parallel angular momentum component
 Sy Perpendicular a.m. component
 Sx Perpendicular a.m. component




Build an NMR Pound box (only three
transistors, and three diodes!)
Mix a sample of water (with a little copper
sulfate to make it blue).
Insert sample in ~3300 Gauss magnetic field
(permanent magnet or small electromagnet)
Observe absorption of R.F. energy ~13 MHz.




Vary magnetic field, observe proportional
change in RF frequency.
Students can see quantum behavior in the
most familiar substance – water.
Students can then experiment with gyroscope
to see quite analogous behavior between the
classical and quantum versions of angular
momentum.



Quantum concepts can be made accessible
early in the physics curriculum, but a
quantum system with strong parallels to
classical behavior is needed.
The gyroscope and the proton of water (H2O)
fulfill this criterion.
A lab can be provided with simple (homebuilt) equipment to show the proton’s
quantum transition (magnetic resonance).



Pauling, L.; Wilson, E.B. Jr. Introduction to
Quantum Mechanics, McGraw-Hill (1935).
http://hyperphysics.phyastr.gsu.edu/hbase/quantum/pbox.html (and
linked pages).
Wertz, J.E.,Bolton, J.R., Electron Spin
Resonance, McGraw-Hill (1972).