Major ideas
1. Light as a particle (photons): When light interacts with matter, energy is transferred in quantized amounts proportional to the frequency of the light. This creates a model in which electrons ejected from a metal surface have energy that grows linearly with the frequency of the light and is independent of the intensity of the light.
2. Conservation of Energy: The overall accounting of energy exchange includes the existence of a "work function" that describes the energy needed to free electrons from energy states within a metal. A deeper analysis relates the work function to the quantum description of the band structure of metals.
Optional: Band Theory of Metals
Major equipment
1. Photodiode: Phototube consisting of a cathode surface from which electrons are emitted, an anode that collects electrons, an evacuated glass envelope through which light can pass, and electrode feed-throughs that allow biasing potentials and current measurement.
2. Optical Filters: Different wavelengths needed in this experiment are produced by a mercury (Hg) vapor lamp. Narrow band fixed wavelength optical filters are inserted between the Hg lamp and the phototube.
Optional: Quartz Mercury Tube, Mercury Spectrum, Picoammeter, Computer control
Data analysis
1. Linear Regression Analysis
2. Data correction (“rectification”) due to the reverse current.
Optional: Python Curve-Fitting
See attached documents below.
See attached documents below.
Apparatus
See attached documents below.
General background and further reading.
See references contained in the list: https://sites.google.com/site/physicslabrefs/home/06-fundamental-quantum-behavior#anchor%201