1. Laser Levitation Project
Stanford University
Summer 2011

2. What is light?
Light is an Electromagnetic Wave traveling in space. Light has all the usual wave properties such as Refraction, Diffraction and wave Interference.
In some situation, light behaves like a stream of particles as observed in the Photoelectric Effect.
We called this the wave particle duality nature of light.

3. What is Laser?
LASER = Light Amplification by Stimulated Emission of Radiation
Laser is a type of light that is coherent and monochromatic (single frequency) useful in many applications.

4. What is radiation pressure?
Light falling on an object, exerts a very feeble force per unit area, pressure, not measurable in normal situations. However for very small objects with higher area to mass ratio, this force is significant.
How does a Laser levitate a glass sphere?

5. Applications of Radiation Pressure:
Optical tweezer: Laser beams are used to move very small objects including living bacteria and virus.
Manipulation of Yeast cells
Solar Sail: Spacecraft in outer space can be propelled using the radiation pressure from sun light.
Ikarus spacecraft, solar sail deployed, en route to Venus, then the nearest star.

6. Laser Levitation setup in lab.

7. Vacuum Chamber to be used later

8. 1 micron glass beads under microscope at 400x

9. Laser beam at focal point