Key Points
- Quantum wavepacket can be represented by a guassian
distribution in space as an approximation.
- Fourier transform of a guassian is a guassian and so
the frequency representation is also a guassian.
- This tells us that dx * dp ~ h and this is called the
uncertianity principle.
- We can define group and phase velocities for the
electron wave.
- Electrons are dispersive.
Questions
- Why do we use a guassian aproximation to a electron
wavepacket?
- What is the uncertianity principle and what does is
mean?
- What are group and phase velocities and when does
dispersion occur?